Decide whether you want your hammock to receive sunlight or shade. Scope out potential areas in that can facilitate the placement and desired use of your hammock. Look for sturdy hardwood trees, such as maples or oaks. Measure the circumference of the trees with a tape measure to find trunks with a circumference of at least 36 inches.
Spread your hammock out, including the hanging ropes, chains and hooks, and measure its total length. Choose two trees situated at least 2/3 of the total hammock length apart. Line a tape measure against the tree trunk, and measure at least 6 feet up from the ground on the side of the tree trunk that faces the opposite tree trunk. Mark the spot with chalk or spray paint to represent where to install the hammock screw hooks or tree straps. Repeat the process on the other tree trunk.
Drill a three-sixteenths-inch-deep starter hole at the marked spot on each tree trunk, ensuring your drill bit creates a hole half the diameter of the hammock screw hook. Twist the screw ends of the hammock hooks into the drill holes by hand until the eye of the hook sits against the tree trunk. If you don't wish to drill holes, another option is to wrap a tree strap around each trunk at the same height, pulling the attached ring through the loop to fasten the strap in place.
Connect an S-hook to the hammock ring or chain on each end of the hammock and the tree hook or tree strap ring. Ease into your hammock from a sitting position first.