I'm no expert, siraniko lang.

You adjust valves pag naka TDC. Start with No 1. Its the one nearest to the flywheel. After adjusting no 1, rotate the flywheel so no 2 is in TDC position. Adjust no 2 and so on until you finish with the last one.

I know there are shortcuts but its beyond what I know.

Pls correct if I said something wrong.