What type of pedal do you have? If it requires an Allen key, they cost less than $2 in a hardware store... My pedals use a 8mm Once you have the right tool, it is relatively easy. You'll also want some grease/lube to put on the pedal thread (so it will come out next time). It can be hard to take them out sometimes. Just remember that they are tightened in the direction you pedal.