Every time I build a circuit from schematic, I put the sockets and major components in place, then wire the power lines, then the signal lines. It's just a matter of doing them step by step, one at a time.

Steve Brown has done some really great tube amps, so he probably has pointers on how to lay the lines best for noise immunity. Other than that, it's all about staying organized so you don't lose track of where you are.

Please keep us posted. Looks like a great project!