ORIGINAL: Green_Flyer
When building a kit from scratch, what are some of the most importatnt things(not that its not all important)to keep in mind eg: things that cannot be fixed once its put together, things to know in advance as to foresee and take care of during building.
Be aware of the frequent need to build left-hand and right-hand sub-assemblies, and ensure that you do actually end up with one of each rather than two the same.

I find that the easiest way to do that is to lay them out "mirror image" next to each other.