Time to finish your Gecho!
If you received some version of the DIY kit, there is a few things to do, before you can enjoy the music.
Soldering THT components
In the parcel you should have received three black 3.5mm Jack connectors, those are for headphones outputs and pickups input. There is also a magnetic sensor (has 3 leads, looks like a transistor), one or two battery holders (3xAAA or 2xAA+1xAA) and two bronze-finish self tapping screws for mounting the board in the enclosure.