It sounds like you're taking frequent trades (my guess) so I'll share with you how I personally managed my trading in a prop futures setting. I hope its helpful and feel free to follow up if I miss the mark.
1. The first bump is the hardest - 1 to 2 lots. For me, I waited until I was several thousand dollars positive and a couple draw checks in the bank first so that first bump was purely about building up a few thousand dollars in positive equity.
2. Subsequent bumps were strictly on a personal reward basis. My own rule was: 3 Green Day's in a row and I took a bump up. 2 Red Days in a row and I took a bump back to the previous sizing level.
3. I kept a trading journal. I know it's cliche and corny but it works. I kept my sizing bumps in my journal. I also tried to be as brutally honest with myself as I could in the journal. I reviewed my entry, my exit, my analytics, my reasoning, and my emotions. Sincerely that journal was responsible for the consistency increases. It was also a great position management reinforcer. Keep in mind that I am using a mouse, a TT screen, CQG, and later a Bloomberg in this setting. No algos - occasionally an Autospreader.
4. In terms of losses I would usually give up a day but NEVER more than a week. What drove that was that a few years into this adventure I was supporting a family with my trading. You gain perspective when you are paying a mortgage, insurance, tuition, cars, kids, vacations, 401K, etc. etc. out of your trading. In a twisted way the fact that it was no longer just about me really throttled my loss threshold.