There are a few basic electronics tools that will be really helpful in building your synth. These tools can be found in most shops and maker spaces.
A soldering iron melts solder that can be used to fuse small metal components. Quality soldering irons (pictured) are not cheap, but basic soldering wands can be found for as little as $15 and would work just fine for our purposes. careful, hot.
Solder is a fusible metal alloy used to create a permanent electrical bond between metal components. Detail tutorials on soldering can be found on the resources page of this site.
Wire strippers help you cut and strip the plastic casing covering wires. They make fancy wire strippers that have settings for different gauges of wire, but the cheap and simple design (picture) works great.
It’s a good idea to have a pair of small pliers handy. They will be useful in installing components in an enclosure, and can be helpful in holding and manipulating components in tight spaces where fingers can’t fit. They can also be helpful in avoiding burns while soldering.
Helping hands usually include two alligator clips and a magnifying glass. Some people love them and some people hate them. They can be a bit fiddly, but they keep your components in place while soldering. If you have trouble seeing the small parts, the magnifying glass is helpful.