Step 3: solder everythign up.
Solder a separate lead to every hot post and one to every ground on the jacks. take all the grounds from each set of input jacks and solder the ends together into two separate bundles (see picture)
take all the leads and solder them to their respective spots on the switch (see diagram)
Basically I made a quick diagram and added some notes. if theirs any confusion just write a comment.
IMPORTANT!!!! you must use flux when you solder. it helps the solder bind to the metal. your solders will break if you don't