Most common probably is building two left or right wings. Pretty easy to do if you work at a fast pace. Not cutting servo wire holes in all the ribs. You need to constantly be checking for straight wings. I use weights to hold everything down against my flat building bd, pins dont work so well for me. May be better for you though. I also use angled aluminum to make sure the spars are straight if I'm not directly over plans. My most used tool in wing building is my 60"x 2" scale. Its a great strong straight edge. I keep the weights on until the shear webs are in and leading/trailing edge sheeting is done. Lots of 2" spring clamps, and 6" quick grips. If its a simetrical wing, make sure the trailing edge is supported at the right height OR washout is set as needed. Check for straightness at every stage of the build. Theres LOTS of additional advice but it depends on what you are building. It would be better to get specific instead of writing a book in this thread. <g> You'll love building.
Edwin