Step 1: Supplies
you'll need a few things. obvious items like saws and screws I'll leave, assuming you have them already.
you'll need 7 pallets in total that look similar, also in size of pieces. keep five aside. pull the other two apart, well I cut the nails with a hack saw or similar. faster and easier.
Step 2: Putting It Together.
it's as simple as it looks. find a way to anchor down the fence. in my case I screwed on pallet into my garage wall at the bottom and middle. to avoid hitting parts of my wall without studs. once you have the one pallet strongly secured you'll add onto it. note how I haven't added boards to anything. keep your workspace open until you're done. using added boards to the inside of the pallets you'll attach the next three pieces. this is where I should have taken more pictures. I measured out and with a full pallet for a gate I need to cut down the third attached pallet three sections. I haven't and don't drill or damage the concrete I keep the whole thing wedged on the ground and used two by fours for stabilizer. the measure and attach hinges for the gate.
I took two of the boards from the cut up pallets and used it to hold the lock in place for the gate. using a three/eighth drill bit I went a little over am inch deep. allowing the lock to work without having to go into my house wall this time. those boards are held in place by the piping along the side of my house. I don't have another picture, but on the bottom there is a small wheel go hold up and assist the gate with opening and closing.
Step 4: More Cutting.
hopping you don't do what my girlfriend did, which is go fast and without protection. luckily in here case she didn't lose her thumb. only part of it. please be patient and take your time. with the said make a mock up of a 90 degree corner and proceed to lay panels completely covering the amount of area you want. once your done with how far out you want it to go. cut the panels using the 90 as a guide. then you'll attached the individual pieces to your bar corner. I used two by fours to raise it so I could latter add a hand rail and have a flush finishes. once those are screwed or nailed on you'll make a support board to stretch out diangely and in the middle of the bar corner. after that's attached measure a cut a beam to have support. with mine I was able to confidently stand and walk on whole fence. I do that way in case someone is drunk or hanging out it won't fall over. take two more panels this time 3 inches thick and that'll will be the back board to prevent anything from rolling off the back. p.s. use levels for this part. and again be patient.
Step 5: Final Touches.
now this is where panels of same size help. if you want a unique or if my look go ahead and use ones of what ever sizes. since you're working with pallets you'll already have some on there. using those existing boards place and level as you attach your boards until finished. using the two by four and cutting at and 45 degree angle then shortening it to size I made my hand rail. lastly decorate, I used road signs but you can take this in any direction with some paint and decor.