To eat tons of carbs you have to do some combo of the following:
A) Be genetically gifted or take drugs/GDAs
B) Be pretty lean to start off
C) Eat the carbs in few doses (don’t spike blood sugar many times in the day)
D) Move you ass (get a pedometer and or lift multiple times daily
Additionally you can try to spike Glut-4 (through exercise) right before and 90 minutes post meal,.,.,. something similar to the tabata protocol, but slightly less intensive. About 90 seconds of intense exercise (like squat jumps, lunges, etc) should do the trick.