hi alyssa, i did this but i never took pics, i will try to do that tonight.
the number one thing i forgot to do is: peel the wax paper AWAY from the candle when you are done heating! i am such an idiot. my candle looked pretty cool, but i couldnt figure out why it had so many air bubbles. i kept re-heating it and smoothing it out. finally i gave up (it was at about 1:00am the night before the wedding when i started the project!) and left it. when it got lit at the wedding the candle heated up and the whole picture was full of bubbles, you couldnt even see the pic of my grampa i thought "wow no one said that would happen!"
then last week when i went to pick up some stuff from my moms house i found the candle in a box and pulled it out. as i was telling doug about what happened, i noticed that the wax paper was peeling off, so i took one edge and peeled it away and lo-and behold, a fantastic pic of my grampa was perfectly waxed to the candle underneath.
so, maybe i just didnt read the instructions far enough (or too long ago before i tried and i forgot!) but dont forget to take the wax paper AWAY from the candle after you use the heat to take the wax off
alyssa, i used about a 3"x6" pillar candle, maybe a little bigger (whatever the standard size is?) and when i created the picture i just made sure to customize the box size to fit in the dimensions.