Stake in the corners before assembling your tent. Also your tent should be completely flat when inserting the main poles.
If rain is expected the rain fly should be “taught”. In other words keep the material tight so that puddles can’t form.
Never keep your tent near the fire pit. If possible place your tent under a safe tree. This helps keep your tent dry if it rains.
Keeping a footprint or tarp under your tent helps keep moisture out. Even if it doesn’t rain moisture accumulates on grass overnight.