Cuttin down your seat foam is neccesary to easily get your feet over the bike on foot tricks like no footed can cans and indian airs. It also helps to make your grab holes more easily accessible.
1) The first step in doing this is to remove your seat cover. This you can do with a small flat head screw driver and a pair of needle nose pliers.
Pry out each staple and simply pull the cover off.
2) The second step is to draw a line (using a sharpie or other suitable writing utensil) on each side of the seat to act as a guide when cutting through the foam. The seat foam should be around one to two inches thick and should curve slightly at the "V" in the seat (see image above). It is also a good idea to put the seat back on the bike without the seat cover to get a better judgement of how tall you want it, the angles, etc. (below).
3) Now comes the fun part. Using an electric cutting knife (a hack saw or band saw will work, but we've found the turkey knives work best) slowly work your way down the line you've drawn, checking each side of the seat to make sure you're staying on the line.
Once you've got the basic angle cut, go over the seat foam with the knife to 'shave' a little more off where you didn't get the line quite right. (Below)
4) Now its time to sand the foam a little, to smooth out any minor bumps and imperfections. Get some 100 grit sand paper and use a sanding block. Not much effort needed here. Just go over the foam and get the curves smooth... Also, round the edges of the seat slightly. (see below image)
5) Now its time to put the seat cover back on. Using a staple gun, put the front of the seat cover back on and use a couple staples to tack it in. Now it gets a little tough.. with your foam cut down, your seat cover isn't going to fit quite right. You'll have to tighen the center, lowest area of the seat first, that'll be the hardest part to get right. Pull the cover tight in the center of the seat and make sure its aligned on both sides and ends of the seat. Tack it in with a couple staples and then work on the front half of the seat. If the center wasn't done correctly, you'll find out quickly when you go to staple in the front half of the seat. After thats tacked in, all thats left is the rear part of the seat cover, which should pull right into place. You'll find that you have a little slack in the cover which will have to be cut off after stapling.