Do you have experience soldering? If not, I'd suggest that you practice on something else before building a kit.
Do you have good tools? A multimeter, a sharp pair of diagonal cutters, some good needlenose pliers, and a good soldering iron (in addition to whatever screwdrivers, etc.) are a requirement.
The first step is to have a good work area. Collect more than a few small plastic kitchen containers, these are indespensable for organizing parts and subassemblies. Do an inventory of all parts before beginning. Don't rush this step. Make sure you can positively identify each and every part, taking care to learn how to read the values of capacitors, resistors and other parts.
When you begin, remember not to rush things. One great thing about building a kit is that you can often take extra care to get it exactly right compared to a factory-assembled unit. Make sure that read each section completely before starting to assemble, don't read as you go. Double-check each section as you complete it. When you're done, go through each step checking again. Most result problems come from an assembly error. Time spent checking is time saved debugging.
Most of all, have fun. Kits are extremely satisfying.
