Hand sewing wallets, belt pouches, briefcases or knife cases is easy with the correct tools. First you have to mark how far from the edge of the leather you are going to sew. There are several ways of doing this. You could just use a compass from school for running a light line along the edge of the leather. You could also lightly run a scratch awl guided with a ruler to mark a line. However an adjustable creaser will allow you to mark how far the line is to be from edge and run a line along the edge that will be easy to see. If you want the stitching to run in a groove, it will line up straighter and allow the thread to last longer since it will lay below the surface to protect it from friction. The tools used for making grooves are called an adjustable groover (used for most leather craft projects) or a saddle maker's groover (used on heavy harness and thick saddle leather). The bar that makes the groove has a small set screw that adjusts how far from the edge you want your groove. This tool can also be used for making a decorative line along the edge of a project even if it is not sewn. The adjustable groover works great with tooling leather but not well with soft leathers.
Next you have to mark how far the stitches are apart from each other. Just run the overstitcher along the line and the pricks in the wheel will leave dots for where the stitch holes will go. The overstitcher comes in 3 sizes. The higher the number, the more stitches per inch. Size six is a good size to use on your leather craft projects. You now know where to punch the stitch holes with the awl (4 in 1 awl set).
Use the awl to punch slits in the leather. Push the awl straight into the leather. If you have a piece of thick cork (1 " or thicker) you could place the leather on the cork and push the leather through the leather into the cork backing. Without cork you have two other options. You could lift the leather slightly off the table and push the awl through the leather being careful not to stab your fingers. You could also clamp the leather in a lacing stitching pony and push the awl horizontally through the leather. With the pony, you sit on the base and the clamp comes up between your legs. It also helps if you put a piece of scrap leather inside the clamp so the wood will not mark the leather. When pushing the awl through the leather, the alignment of slits should be at 45 degrees to the edge of the leather ( ////////) as opposed to parallel to the edge (- - - - - -). If the slits are parallel to the edge, it could tear since it would act like a perforation in paper.
If you don't want to use an awl to punch the holes, you could use the diamond hole punch which punches angled slits. Place the leather on a cutting board or poundo board. Make sure it is on a solid surface that has no bounce. Hit the diamond hole punch with a rawhide or polly head mallet. A metal hammer will tend to mushroom the top of the tool over time. This tool would be easier to use than the awl as you can punch four slits at a time. For tight curves you can use the single diamond hole punch.
If you are making a hunting knife case and have a top layer of leather, bottom layer of leather and a middle layer (around blade edge so it won't cut thread), you would find it too thick to punch through all three layers at once. You could do them individually but that is a lot of work. Although this other method I am about to describe might not be proper leather making etiquette, it works. Before we had industrial sewing machines, we used to glue the layers together and do the marking as previously described. However, to get through all three layers we used a hand drill with a drill bit that was just a little bigger than the needle. If you have a drill press, it would work better than a hand drill because all the holes would be perfectly perpendicular to the leather.
Now that all the holes are punched you are ready to sew. Put a harness needle at each end of your waxed thread and pull the thread halfway through the leather. Next put the needle through the next hole and pull the thread though all the way. Take the other needle and put it through the same hole from the opposite side and pull both threads tight. Continue this method to the end of the slits. At the end of the slits do the same procedure back about 6 slits and you can cut the thread without tying knots as it will not come undone. You can use the number 0 harness needle if you are using the waxed thread from the awl reel or the bigger number 000 needle if you are using the 25 yard waxed thread which is slightly heavier. If the thread is frayed a bit when you try to put it through the eye of the needle, just rub some beeswax over the end to hold it together.
To keep the stitch looking as neat as possible, keep putting the needle through always on top or always on the bottom of the other thread as opposed to sometimes on top of the slit and sometimes on the bottom of the slit. If you find it hard to push the needle though, you can push it part way though while wearing a sewing palm or pull it through with needle nose pliers.
If you don't want to use harness needles to sew, you could use the lockstitch sewing awl. The awl needles for the lockstitch sewing awl are not strong enough to push through heavy leather without punching slits first as discussed earlier. If it is a very thin leather, you could get by without punching the holes first when using the lockstitch sewing awl. Personally I find it easier to sew with the harness needles but a lot a people like the lockstitch sewing awl for doing general leather repairs.
First mark how far from the edge the lace holes will be by pushing the adjustable creaser along the edge of the leather. You could also run the scratch all along a ruler to mark a line in the leather.
Next you will need to punch slits in the leather for the lace. Put the leather on a cutting board or protecto board so that the edge of the chisels will have something to go into that will not damage the end of the tool. It works best on a solid surface that has no bounce. Line up the 1 prong, 4 prong or 8 prong chisel on the line and hit it with a rawhide or poly head mallet. On sharp curves you would have to use the single prong chisel and on straight runs use the 8 prong chisel or 4 prong chisel to save time.
If you do not want to punch slits for the lace you could use the 4-in-1 punch to punch round holes. For going around curves you could punch individual round holes with the mini leather hole punch.
There are two common needles used for holding the Tejas Superior Calf Wallet Lace which are the loc eye (Hook-N-Eye) needle and the 2 Prong Lacing Needles. Thin the lace thickness with a utility knife or a French edge skiving tool in order to fit it between the spring of the 2 prong lacing needle. You can squeeze it tight with some needle nose pliers being careful not to bend the prongs. I personally prefer using the hook-n-eye needle because I find the lace is less apt to pull free from the needle when you are lacing. With the hook-n-eye needle, you need to narrow the width of the leather so it can fit through the eye of the needle. You should also thin the lace so it can fit between the needle spring. Then squeeze the spring tight with needle nose pliers being careful not to bend the hook (prong).
Projects such as wallets require a lot of lace if you are doing a fancy lace edge. Because you do not want to pull yards and yards of lace through every slot, you might want to lace the wallet with 3 or 4 lengths of lace that you join together when you are almost at the end of the lace. To do this, you need to splice the each end for about one inch to a feathered end. You could use a utility knife or craftool French edge skiving tool to splice the lace. Put a quality contact cement on each piece. When the contact cement is almost dry to the touch, squeeze them together and then tap them with a hammer on a mini anvil. You have to be careful when you pull the jointed pieces through the hole / slit to make sure you do not tear the joint apart.
Up to this point I have been discussing lacing with the Tejas superior calf lace which is commonly used lace when lacing a wallet or other similar leather craft projects. If you want to lace using a heavy lace like a leather shoe lace for bigger projects like briefcases or purses, you will have to punch larger round holes with the mini punch. As mentioned before, put the leather on a protecto board or cutting board to make the cutting edge of the hole punch last longer. Sometimes we just put a piece of scrap leather under the leather project when using round hole punch to protect the cutting edge if the cutting board isn't handy. An easy way to pull this heavy lace through the holes is to use a jumbo perma lok needle. Cut the lace narrower and to a pointat one end with your utility knife. Take this pointed end of the lace and twist it into the end of the perma lok needle. The hole in the end of this needle is threaded to grip the leather lace.