This is an easy trophy for getting stung by the bees on any of the two levels - Diggin it or Bee-Having, both of these levels are in the fourth warp room up.
All you have to do as you progress through any of these two levels is find one of the many bee hives on the level, wait for the bees to come out of the hive and let them attack you.
When this happens Crash will inflate like a balloon and you will unlock the trophy.