new to relays,need wiring tips

i havent used relays too much so i cant get the grasp down on them.does everything basically get hooked up the same.85 most of the time goes to ground?87 is mostly 12v power,or is every situation different.i would really appreciate any wiring tips,diagrams,etc.thanks

85 and 86 are the low current coil connections of the relay. Power to 86 and ground to 85 energizes the relay. With no voltage on 86 or no ground on 85, the relay is at rest. At rest, terminal 30 (the common connection) is connected to terminal 87a (the normally closed connection). When the relay is energized terminal 30 is now connected to terminal 87 (the normally Open connection). Read this page And This

thanks for the links.lots of very useful info