8.2 Indicating Line Of Play
Except on the putting green, a player may have the line of play indicated to him by anyone, but no one may be positioned by the player on or close to the line or an extension of the line beyond the hole while the stroke is being made. Any mark placed by the player or with his knowledge to indicate the line must be removed before the stroke is made.
I often have problems with my alignment. I presume it is okay to place a club down AFTER playing your shot on the fairway or the green? I have been doing this recently but cannot find anything in the rules.