How to reduce EMI EMC in PCB?
If you have any bypass or decoupling capacitors in your PCB design, connecting them directly to the ground plane will help reduce EMI. Grounding these capacitors quickly ensures that return currents have a very short path to complete their loop.
Can I design my own PCB?
When you are going to design your own PCB, you need to draw holes, pads and wires for your circuit. Then you send this drawing to a manufacturer or you etch it yourself. Before you start drawing wires and stuff, you need to know what circuit you want to build. So you need to find or design schematics for your circuit.