Knowing when to say when

[LUCKYDOG]

what is a good indicator, outside of removing the plant from the pot, to pot-up. ie drooping leaves, stunted growth, ??? and how big of a pot the next size say from 3 gallon to 5 gallon or pot for the last time all together? :?:

[POTAWIE]

When the plants dry out quickly and fall over easily then repot or if you see lots of roots coming out the bottoms. I like to pot up gradually and never go straight into a big pot from a small one.