The easy way to make a trellis is to use 6-foot metal posts and galvanised wire, nylon rope or netting which are all available from Home Depot of Lowes. Simply pound the posts in the ground about 18 inches and connect them with the wire or rope at 1 foot intervals. Recommend a post every 6 feet. Alternatively you can use wooden lattice instead of wire/rope and 4X4s instead of metal posts. In that case you will need a posthole digger to dig holes for the 4X4s.

I decided to go with a wooden lattice, I found the Ideal size for 2 squash plants, a 2x4, and I'm just going to stick it in the ground just in the middle of the 2 plants.