1 Download and read the build manual.
2When the kit arrives you will want to sort the hardware into some kind of organizer tray..
do some sort of inventory to insure all the parts are there. If you are going to build right away fine you will notice missing parts if the kit will sit for weeks or months do a full inventory.
It would not hurt to test the power supply check voltage and if you can put a load on it make sure the cooling fan comes on.
Make sure you tool set is in order there are lots of metric fasteners so metric hex keys and mini metric wrenches come to mind.
Safe wiring is important you may want to get appropriate crimping tools and connectors sets. wire ferrules on the end of wire are good practice. also a supply of heat shrink and wire loom can be helpful as are wire ties.