easy. DON’T BE AFRAID OF FAT!
I’m currently gaining weight and eating low-carb… not the fastest way to gain, but for me it’s helped minimize fat accumulation.
Training days tend to see more carbs (200-300g), while off days are low (100g or less).
Regardless of amount, i eat carbs in the morning and pre/post workout, and fats (with little or no carbs) throughout the rest of the day. All meals have protein.
As far as ratios go, fat (mostly from olive oil) is anywhere between 40-50% of calories for the day. Protein is around 40%, and carbs tend to be between 10-20%. It’s been working well so far.