I am sure there are people on here way more knowledgeable than myself and can give some very detailed tactics. Yet from my perspective it really boils down to the following:

1. Easiest way to avoid dilution it is to not take any VC money.

2. If you have to take it to grow and you are profitable with a strong history of growth then you are in the drivers seat and can negotiate better terms.

Other than that you will generally get diluted down for every round of funding you due outside of a small seed round.