Ok hooking up a hot tub is ez. Check the nameplate to see the minimum circuit size (probably 30A). If so, use 10 copper stranded wire for the 2 hot wires and the neutral (if needed), and run it through some 3/4 schedule 40 (grey electrical pvc) pipe. If going underground bury it at least 18" down to the top of the pipe in the trench. Mount a gfci 30A disconnect and run the pipe into it. If you don't have a solid mounting spot for the dc, try a chunk of treated 4x4 with about 2 ft down in the ground and 2 or 3 ft sticking above ground.. After you have the pipe run from the breaker panel to the dc, pull in 3 cut pieces of #10 stranded copper wire, one in its black insulation, one with red tape on it (on both ends) and the last with white tape on both ends. Also run a piece of #12 with green tape on both ends. Make sure you cut the wire plenty long. You should end up with about a foot sticking out of the pipe coming into the dc, and 3 or 4 ft sticking out of the pipe going into the panel. Install a new 30A 2 pole breaker in your panel. Go outside and terminate the wires into the dc. Black-line 1, red-line 2, white (if needed) to neutral bar, and the green #12 to the ground bar (separate bar from the neutral bar. Now terminate the wires coming from the tub into the dc. After they are all tight and the dc is closed back up, go inside and terminate the wires in the panel. Black and red #10 to the breaker, white to neutral bar, and the green to the ground bar.