Clean everything, degrease stuff you about to be wrenchin.
Wash off mud if its under the car, use that wire brush.
Clean bolt heads ,perhaps some WD40 to soak while preparing area.

Sounds boring but it's just a good practice.

Wanna start working on your car? Here is what your toolbox should contain. 

Combination wrench set (6/7/8/10/11/13/15/17/19)
Pliers (Combination/needle nose/cutting/channellock)
1/4 socket set (5-13) with bits (allen/torx/phillips/flathead)
1/2 socket set (10-32)
Flathead screwdriver big and small one
Bit screwdriver
Hammer
WD40 and zip ties