My Da explained the offside rule to me during the 1966 World Cup... but here's another explanation that you may find useful...
Imagine your in Primark, queueing in single file, the girl in front of you doesn't have her purse, to your dismay you then realise you don't have yours either.
A solution is that your friend towards the back of the queue is offering to throw her purse to you, but you can't queue jump until the purse has been thrown to you,
Once the purse has been thrown, you can quickly dodge the girl in front, then pay the girl at the desk.
WORDS THAT GO BUMP IN THE NIGHT
figs