Various Gameplay Tips
Simply play as often as possible to get the wanted results.
As your character loses weight, the rope tends to speed up very very slowly, so it won't be enough to make a meaningful difference for a long while, but it certainly makes enough of a difference.
Obvious tip is that you need one energy drink in order to play one round, but when you run out of energy drinks you need to pay some real money for them.
The alternative is time lapse cheat: go to the date and time settings on your phone, set the time ahead, and then go back to the game and start a round.
Your character gets fatter if you go for awhile without playing the game so use time cheat carefully since it will add more weight to your character.
There are four power ups in this game: The energy drink that replenish your energy ; The candy will lower the speed of your rope making it easier to jump; The can of spinach will make you strip and lose weight at double the speed; The healthy bar will stop your character from gaining weight when you can't play the game for awhile.
Various strategies
Tap in succession as your character jumps rope. The more times you are successful, the more his weight drops from 400 pounds. The rope speeds up occasionally, requiring you to adjust your rhythm.