Collecting all gold tokens is an easy, if slightly annoying trophy. This trophy will most likely require two playthroughs. The excellent part of this is that you can revisit any level you want to at any time to find the tokens you've missed. The catch is that you have to replay the level all the way to the end or any tokens you find will be lost. However, you do not have to recollect every token, only the ones you missed. There are 100 tokens across all 5 dimensions, but only certain levels have 5 tokens.

Take a look at the following guide by migueloetb which will help you locate them: Gold Tokens Locations Text Guide.