How to keep character facing 3/4 front when moving right and left in 2.5D game

I am having trouble figuring out how to "Cheat" my character movement in a 2.5D platformer game by having the character walk in a 3/4 front position while moving right and left. I am having trouble figuring out the best approach for this. Should I rotate by a certain number of degrees when the character is going in a specified direction? And if so what is the best way to construct the script in javascript? Thank you very much, I hope someone understands my rambling and is able to help me in my quest of learning.