There are a lot of connections that need to be made.  Using a combination of solid core wire and stranded wire is the easiest way to get everything packed into as small a footprint as possible.  

Color coding is your friend here!  Keep your power wires all red and ground wires all black, and use a variety of colors for the other connections so you don't get confused.  Write down the colors you used and the corresponding pins they connect with so you have a quick reference you can use while soldering.