ill make a tutorial one of these days, but ill try to explain it as best as i can.minimal tools needed- spade shovel- 1, 12inch tire spooon- 2or 3 flat head screw drivers, electrical tape, dawn soap and a sponge.
1. take the rim off the bike
2. either take the valve core out or slash the tire
3. take your dawn soap,water and sponge and wet the whole bead
4. take the spade shovel place the tip in the bead and jump on the shovel(do this on bolth sides if the rim)
5. take your tire spoons and screwdrivers and wrap the ends
6. press the tire in the center of the rim (you have to keep the tire in the center so kneel on the edge of the tire) and pry with the tire spoon and screw drivers and work your way around
7. now that you have one side off use the tire spoon again and go from the inside of the rim(i.e inside the tire) and pry on the outside edge of the rim(remember to use that soap and water) and it should just slip right off with some force.
now that you have the tire off now its time to put the new one on you can get rid of the shovel now
1. wet the outside and inside of the rim and tire with the soapy water
2. depending on what kind of tire you buy there should be some sot of yellow/orange dot on either side of it, that where you like it up with the valve stem and of course make you have it in the right direction
3. now that you have that figured out you should be able to slip the tire on over the out side of the rim , so now you have one side of the tire in the rim and one side of it out
4. on the part of the tire that is out side , start pressing it in as much as you can without any tools(using your knees depressing the tire in the center of the rim) now when you cant go any further. start using the tool
5. use the tire spoon to pry the tire in and use the screw driver to hold the tire on( start from the ouside and work your way in)remeber to use those knees too it will make it alot easier.
hope this helps some what.