It looks hard and annoying but it's not with these small tips.
*There is no time limit so you can take your time.
*You can quit out and continue later on.
*There are unlimited puzzle boxes you can collect pieces in, thus you can collect pieces for the outer frame, colored pieces, numbers, buildings and whatnot.
*50 % of all the trouble can be taken out by doing the puzzles from the Kid's Pack, which is the cheaptest and easiest pack of puzzles aimed at (DUH!) kids.
*Kid's Pack starts with 12 pieces for the easiest, 20 on medium, 35 on hard, 48 on expert, 108 on master and 192 on grand master.
*Easiest and least pieces (about 96 per puzzle) can be found in the free Fable Anniversary pack.
*To make this a bit easier, on the right you have several options. One of them is "arrange", which selects all pieces and puts them in 3 parts, with the outer frame apart and the other pieces in two parts.
Easiest puzzles after Kids Pack are the puzzles in Food Pack, which are 96 or 108 pieces on hard.