well its actually very easy. you set the tire on the rim (be sure you have the side you want to face out the right way or you get to do this all over again!) tilt the tire so that the bead can get its start on the rim. use your knee and hold that part down. and just start working your way around.

you'll get to a point where its just impossible to get any more on the rim by hand. Then you just need a big flat tip screwdriver, or a small pry bar. Slowly keep prying the bead over the rim (if you try and pry too much onto the rim at one time you could damage the bead, so take it slow. eventually the entire bead will be on the rim, then you need to do it again for the other bead (2 beads per tires).

Then it works best if you can set the tire/rim on something so its off the ground (lying flat, valve stem up) hook up your air and you may have to try and nudge the tire up a little near the valve stem to get it to start filling. once it starts filling , it will SNAP into place, then just put the pressure to your desire, and head off to the balancing shop.

Keep in mind this was done on a steel rim, can be done on aluminum too, but the risk of scratching it is greater. SO if they are brand new rims, you may want to have them done at a shop! Otherwise, give it a shot, nothing to lose, if you can't get it, just take em to the shop!