The major trick, IMHO, is not to grow.

While a "normal" startup is focused on growing! growing! growing! a small company should instead think like a physical restaurant:

"I have 10 tables * 4 seats. 4 waiters. Operate Lu-Fri 10 am - 6 pm. I can serve only up to 40 customers max per hour. My income will never be bigger than 40* Average meal. My income needs to be at minimum Costs + 3% profits".

Then you see you have too many waiters. You cut it to 2.

Then you see your meals are too cheap. You increase it a little.

Then you see you have little customers. You grow a little.

Then you see you have TOO MUCH customers. You stop growing. More costly take-over, increase the cost of the meal, etc.

What you NOT MUST DO is grow more than your max capacity.

That is it.

Size your capacity. Figure a nice profit. Keep it small.