Numpty alert - do I need rim tape.?

Follow these steps and you'll be fine:

1. Fit rim tape
   
2. Check inside of tyre for foreign objects/damage, exposed wire (if wired tyres) etc
   
3. Fit new tube and put a very little bit of air into it - check to ensure that you aren't pinching the tube between the rim and sidewall before fully inflating to recommended pressure.
   
4. Ensure retaining nut is done up firmly on valve stem
   
   

Ride it.