The basic tools for building the simplest transmitter:

Soldering Iron (20-30W type; don't use a powerful one such as 60W. It will destroy the parts.)

Solder (Usually this is sold as a roll but you need only 30 cm for one set to build).

Tweezers

Small Wire Cutter

Five-Minute Epoxy (the strongest type for metal and chinaware to glue)(Instead, you can use "Double sticky" or "Double coated tape" too.)