I need some help screaming pleasepleaseplease?

okay, so vocalist for my band , and i can kinda scream, but not that well yet, we do stuff like bfmv, black veil brides, etc. like i said, i can kinda scream but not really that well yet. my scream is quite soft and i want to make it louder and have a more coarse sound if that makes sense :/ btw i exhale and use the air from my stomach, thanks for your help ;D