Like others are saying, pay it off every month. Ideally, you’ll want to keep the usage around 10-30% max. If you have a $5000 limit, that would be a monthly usage of $500-$1500. If you max it out, banks will assume that you’re a risk and will ding your score.
Keeping it below 30% will also help grow your limit. Banks will periodically up it. This is also based on reported income, but from experience, if you have a low limit and max it every month, they will not really increase your limit.