DIY power suppy

What do you need?

Old working PC power supply (second hand)
Buck/boost converter module LINK eBay
2 x 10K ohms potentiometers LINK eBay
2 x plastic knob LINK eBay
1 voltmeter/ammeter module LINK eBay
Banana connectors LINK eBay
2 x toogle switches LINK eBay
1 LED LINK eBay
Wires
Shrinking tubes LINK eBay