I just got my first personal credit card 8 months ago, and I'm occasionally hitting/getting close to the credit limit. I've never missed a payment or had to pay a single fee, and I'm using the card for everything. 

I tried to get my credit limit boosted two months ago and it was boosted a couple hundred bucks, but it barely solves the problem; I still have to manually pay off my balance instead of waiting for my automatic, monthly payments. This was the only time I requested a limit raise (and it was successful, but not for the amount I requested).

I want to get my limit boosted as soon as possible, but how often should I request a boost? Will it negatively impact my ability to raise my limit if I request a limit raise too soon after my last request?

My current limit is low. My typical utilization is ~50% or more at statement time which I know is high and could affect my credit rating. Sometimes I've had to manually pay my statement, and this month I had a charge declined because I hit the ceiling for the first time (neglected to check my limit before a large purchase).

My credit card is my only "debt", student loans paid off, I own my car outright. Renting house, no mortgage.