Take off your undergarment throw it by one wall. Assuming the room has 4 walls this is your marker for wall "0". The rest of the walls going counter-clockwise

Take off your undergarment throw it by one wall. Assuming the room has 4 walls this is your marker for wall "0". The rest of the walls going counter-clockwise will be walls "1", "2" and "3". Close your eyes and spin in the room until you lose your orientation then stop and open your eyes. Record the number of the wall you are facing in your head. Repeat spin and remember next new number. Repeat spin and remember next new number. Repeat, repeat, repeat until you have reached the maximum amount of numbers you can remember sequentially. You will have a sequence like 2,1,3,0,2. Take your numbers, concatenate them sequentially, and translate from base 4 (ex. 21302) to base 10 (ex. 626)