checking oil with dipstick
 

This is a dumb question but im on the road right now and I dont have the manual. When checking the oil I understand the car needs to be warmed up and on a flat surface but does it need to be on or off.

2004 530i.

The car should be off. Actually, the oil level should be measured after the car has sat for awhile so that the oil has had a chance to sink to its lowest point.