If your watch loses or gains a few seconds per day (remember there are 86,400 seconds in 24 hours !), you can correct it without expert aid.
The rate of a watch varies slightly depending upon its position. Take it off at night and place it as follows:
1) To gain a few seconds
Lay the watch flat with the dial uppermost
2) To lose a few seconds
Lay the watch vertically with the winding-button downwards
3) To lose rather more seconds
Lay the watch vertically with the winding-button uppermost