Pick and order your parts. If you live in (shithole nowhere), wait months for them all to arrive.
Measure and drill holes for landing gear, gimbal, video tx, mounting posts, and wiring.
Use good double sided tape to fix components.
The motor screws were too short to comfortably fit through the mounting plate and frame body. I ended up compressing the screw holes into the wooden mounting plate.
Customize wiring harness and run all wiring. I used small cable ties keep the ESC's in the arm of the body, as far away as easily possible from the other electronics. An improvement would be to use slim ESC's and trim the wires to the minimum lengths.