Quick and dirty: Take measurement from top of wheel arch to ground on both sides and record the numbers. Follow the long cylindrical rods from the lower control arms back, just rear of the center of the truck, where they end with an adjusting bolt. Put reference marks on the bolt head and a stationary part. Tighten the right and left sides an equal number of turns and check clearance, repeat until satisfied. Record the number of turns in case you want to return to stock specs. It's something like 8 full bolt turns=1" of lift.

Get an alignment.

If you do a search I'm sure you'll find more info on this.

Good luck