Practice makes perfect. Wood or any other nonconducting material will work fine. Then cut to side of holes. Loop No 20 bus wire around folded dipole and through mounting holes and twist tight on other side to secure. Mounting holes for folded dipole.
All tops slope in the same direction.
See Figure 5 for element mounting details. You can glue or screw the dipole mounts to the base if your materials permit. Elements are tied to the mounts with bare wire and secured by soldering. This reinforcement is essential where you will be clamping or drilling. See Figures 7 and 8 for details.