Use Google Maps, print off some central Beijing maps and take with you prior to travel.

Wednesday: With a roughly on-time arrival at noon, you should be through any arrival hoops and out to transportation options by 12:45. Assuming you take a taxi, traffic shouldn't be too bad and you should be to your hostel before 2 pm. Get checked-in and avoid the temptation to lie around.

Activity: Do it yourself walking, at your own pace. I'd recommend starting in your hutong neighborhood for a few minutes, then walking to the nearest main intersection corner (where Dongsi subway station is) and continue walking west until you get to the back of the Forbidden City and Jingshan Park opposite. If the day is clear, go into the Park and up the hill for a great view. Then down and continue your walk a short distance westbound to the south gate of Beihai Park. Enter and walk around the lake towards the north. Stop for a look by the Nine-Dragon Screen and the little building complex with rock garden in the back. Exit Beihai Park out the north gate. Cross the big boulevard to the other side and head into the old hutong area in the Houhai District. By now it will be late afternoon (estim 5:30-ish) and getting interesting, with the residents puttering about the alleys around the old courtyard homes, and the restaurants and bars around the lake ramping up for business. Pick a place and eat. Then if it's not dark yet, head to the Drum Tower for a look from the outside, then head back to your hostel by taxi. Get to bed relatively early, jet lag (assuming you're coming from the USA) won't be that much of an issue but fatigue will.

Thursday: Try to get up around 6 a.m. and get a taxi to Tiantan South Gate. Remember: South Gate. There's a public park between the road/taxi drop point and Tiantan proper, in which lots of locals will be doing their morning activities, worth a look. Then continue into Tiantan proper to take a look at the Temple of Heaven, Echo Wall, etc. Head out the East Gate where you'll find Line 5 Subway Stop, go north 2 stops to Chongwenmen and switch to Line 2, one stop to Qianmen. Get off and use Exit C. You'll be on the south side of the Arrow Tower at the south end of Tiananmen Square. Photo shoot and walk your way around the periphery of the Square. Up to you whether you want to stand in line for Mao Mausoleum (must check bags at counter of building opposite on the east side of square), or the National Museum. Work your way around to Tiananmen and the portrait of Mao. There are some spots to eat and snack in the vicinity but most of them are on the Qianmen side. Then head inside to the Forbidden City. Ticket booth for the FC is not when you first pass under gate by Mao portrait, but is to the back. When you've gone almost as far as you can go before running into the big gate and ticket check, look to your left and you'll see the ticket booth off to the side. Rent Audioguide if you want (English available). Go into FC and work your way around, expect it to take 2-3 hours.

This will be most of Thursday. By late afternoon, you might want to head back to hostel for a short rest, or head over to expat side, maybe Sanlitun or one of the hotels often mentioned here for drinks, etc. Maybe an FT'er will be around (I'm in USA now or I'd offer to meet up.).

Friday: Try to leave around 7:30 am and get a taxi to the Summer Palace, which may take about 45 minutes. Wait until 8:30 and it may take twice as long. Go to the East Gate. Enter and wander around. You can research from a guidebook. Most of the buildings are on the East and North side, so I suggest you concentrate your time there, then head out the back of the north side where the gardens are. Also the north gate which is closest to a Line 4 Subway Stop. I presume that it will now be around noon. Go south and get off at Xizhimen station, switch to Subway Line 2 and head east to Lama Temple (Yonghegong). Hop off and head towards the entrance. There are a number of good snack shops and decent restaurants around there, so have lunch before heading to the Temple itself. If you have additional time (depending on how late in the afternoon it is), you may want to either head to the nearby Confucius Temple, or down to the Drum Tower area again, or just wander hutongs back south until you get to your hostel.

For a domestic flight at Saturday noon from T3, I'd leave the hostel about 9:30-9:45 a.m. It shouldn't take more than an hour by taxi to get to T3, might be less. Another option if not heavily loaded with luggage is to taxi over to Dongzhimen Transport Hub then take the Airport Express out.

Massages can be done on Thursday or Friday evening (or both!). Search this forum for recommendations, most of them are in the part of town east of your hostel but not horribly far away, perhaps block out time for dinner and massage or viceversa in that part of town, returning to hostel later by taxi.

Second round arrival at Friday 2 pm--no shouldn't be too bad and if you are coming in on domestic, won't have to deal with Immy/Customs so should be able to grab bags and head out to taxi queue, hopefully getting to hostel by 3:30 pm when the ugly Friday aft traffic kicks in.

For the Saturday full day, earmark it for the Great Wall. Which will be either a 1/2 or full day depending where you choose to go.

There you are.