For the future!

With IT and wiring, you really need to document everything that you do for the idiot that will be there in five years. Especially if that idiot could be yourself.

What you need to pull off a medium-big wiring gig
You'll eventually build up a kit full of tools you like. This list is pretty off-the-cuff, and a decent start.

• Ladders, fiberglass. I enjoy having one four-foot and at least one each of six- and eight-foot. You will move a ladder often, so don't get anything too heavy.
• Electrician's tape, many many rolls of black, a few extra rolls of "other." White never hurts because you can easily write on it; day-glo whatever never hurts because you can see it in dark crawlspaces.
  
• Sharpies.
• Wire cutters, aka "dikes."
• Good scissors, aka "snips."
• Boxes of cable, probably category 5e and probably plenum.
• Patch panels. Don't get crummy ones; these things will probably outlast you. Think six times before you mount them, since once you punch down, you will never want to move them.
  
• Sharpies, fine tip.
  
• RJ-45 heads, lots.
• Crimping tools.
  
• Wall plates, various sizes. I currently like the keystone-style blanks so you can pop in different colored jacks or blanks or coax or RJ-11 as needed.
  
• A bucket of pull-string. Two colors is fun, but overkill. If you remotely intend to mark different things with different colored string, rethink everything.
  
• At least one cheap toner and wand per person.
• A fancy Fluke meter. If you can, get the fancier one.
• A whole box of miscellaneous screws.
• Cordless drills, non-sucky. Also get extra batteries and a charger.
• Screwdrivers, various.
  
• More sharpies, and pens. Write down as much as you can.
  
• Fish tape. For some reason, this stuff is expensive. It also sucks.
  
• Labelmaker, good. Label extensively.
• A good knife. Maybe two.
  
• Measuring tape. It never hurts.
  
• Punchdown tools.
• Fish sticks. Expect to lose or break at least one, so have extra. Bonus if you don't lose 'em.
  
• Flashlights.
• Batteries. Those Fluke meters, cable testers, radios, you name it will eventually need batteries. Have spare so you don't need to waste an hour on a battery run.

Did I forget anything? Yes. I have no doubt. The moral of this story is be prepared to improvise, and be prepared to make at least one mistake.

Always pull twice as much as you think you need, always, always. The cost of a wiring gig is virtually never the material, but the cost of labor and the calendar time. If they ask for one drop per room, make sure you do two drops. I say overpull unless physical space is a serious concern- for a one-person office, I'd do at least four terminations total. Maybe six. This gives you maximum flexibility in the future: Maybe you put in two people into the office, maybe a printer, maybe you go VOIP with your phone system, maybe you rearrange the furniture.

Wiring shouldn't be an afterthought. Do it when the walls are down.