Using your template or personal design, cut each necessary section of fabric or leather out using a surgical knife or scalpel. You may find it helpful to use a ruler or protractor to help you with the incisions. While cutting your pattern, you should leave at least an inch of extra material along the bottom edge of the shoe, as well as a centimetre or so, where the different pieces of the upper join together. This will be your seam allowance. A fluid stitch is one of the most skill-testing parts of making your own shoe. Be meticulous and slow as you're piecing it together; while it may be easier to go faster, bad stitching will certainly show in the final product, and your shoe won't look as good as it should. Try to get the stitches as close to the end of each piece of fabric as you can. Overlaps might leave unnecessary ridges on the shoe. If you intentionally cut your pieces to be slightly bigger than necessary for the sake of having stitching space, remember to take that into account. You don't want to end up with a shoe that's too big, or too small for the sole. While fabric won't be any problem to stitch through, you may have an issue with leather. Leather is notoriously sturdy, and you won't be able to stitch it fluidly. Rather, it's recommended you punch holes in it before connecting it to your other pieces. Eyelets are the holes you'll need to fix your laces through. Chances are your shoe design will use these. Evenly space the eyelets apart from one another (just less than an inch, in most cases) and offer enough of them (4-5) to encase most of the laces. If you're the DIY type, you can make these incisions with a scalpel easily enough. If you're going for a more professional-looking product however, there are specific eyelet-making tools you can order from a specialty outlet. If you purchased a pre-fabricated sole or nabbed a pair from old shoes, you won't need to worry about this step. If you're trying to make a purely homemade set of shoes however, picking up a few sheets of cork is your best bet. Cork has a comfortable amount of cushion, and it's waterproof.  If you have the fabric stitched together already, you can use that as a point of reference while making your incisions, although you should ultimately rely on the empirical measurements laid out in your template. Your last should come in handy here as well. Cut the sole out of the cork sheet, leaving a little extra space around the last so your foot will ultimately have some breathing room. If you're wanting some extra cushion and height, you can add a second or even third layer of cork to your sole. Just cut it out in the exact same dimensions, and superglue the layers together. Give the glued cork soles some time to solidify once you've finished gluing them. You can make a shoe heel by adding an extra layer to the posterior third of the sole. Stitching the fabric to your sole won't work, at least not by itself. It's recommended you pick up a shoe-specific adhesive to glue your fabric to the sole. Apply the glue slowly and evenly. This will maximize the waterproof seal for your shoe, and keep it sturdy. If your blueprint suggests any additional stitches, do those as well.  Make use of the last inside the shoe as you're putting it together. It will make a great point of reference and support while you're getting the tricky stitches done. If you're a real pro with stitches, don't be afraid to spice up your stitching style. Stitches themselves can be an interesting aesthetic tool. If you're feeling more daring than the rest of us, you can experiment with irregular stitching patterns, so long as they're fundamentally sturdy enough to do their practical job. By this point, you should have relatively functional shoe. Add laces through the eyelets if you haven't already. To make the shoe look as good as it can be, you'll want to trim the excess fabric. If there are some really ugly seam marks on the shoe, you can add a new layer of leather or fabric to cover it up. Now that you have the body of the shoe, you can start thinking about adding more aesthetic flair to it. It's generally assumed you'll want to make two shoes to wear at the same time. After the basics of the first shoe are done, it's time to move onto the second. Keep in mind that you're not wanting to make a copy, but a mirror image of your original shoe. Try to keep it looking as close to the first as you possibly can. Any possible slip ups you made on the first will look worse if they're not reflected on the other shoe. If you were frustrated making the first shoe, you should find making the second is a lot more enjoyable.
Cut out your leather and fabrics. Stitch pieces together. Make eyelets. Cut out your sole. Stitch and glue your pieces together. Trim excess fabric and add patches where desired. Repeat the process for the other shoe.