How do you charge the air conditioner on a Toyota solara?

Without specifying your Solara year and engine type you're going to have to settle for a generic answer. The best way to "charge" your air conditioning system is to drive the car to a shop and whip out the old Amex, Master or Visa card. If your system isn't working it generally means there's something wrong. A seal is allowing refrigerant to leak, something is wrong with the pump, a fuse has blown or maybe some kind of creature just built a nest in a duct. There are do-it-yourself kits available. They all use small cans of R134a and most are available at auto supply stores. Some include a pressure gauge so you know exactly how much coolant to add. The simplest just use a hose to connect the can to the low pressure side (larger of the two metal tubes from the compressor) of the system and you empty the can. That will either work or kill the system with too much pressure (ruin seals). Cheers