In the scene when Wei Lin and Bond were both taking a shower by the water pipes, you could see that Bond had completely taken off his shirt ... how is that possible while you're handcuffed to somebody??
If you notice, unless bond is wearing a special outfit (skiing, skydiving, etc, etc, etc) he always has button up cuff. He could have just unbuttoned the cuff and slipped the shirt through the hole!
Bond Always wears a button-sewn shirt, with button cuffs, and the shirt is still there. He wears-for the record, either a suit, or Sea Island cotton shirts.