The strategy below is the Wizard's simplified strategy for Jacks or Better.  You give up just a tiny part of the return (99.46% instead of 99.54%) and in exchange you get a strategy that's much, much easier to learn and remember than the perfect strategy.  The 0.08% penalty costs you only $0.60 per hour of play on average, assuming a quarter machine played at 600 hands per hour.
A straight is a hand with consecutive ranks, like 9? 7? 10? 8? 6?.  Notice again that the cards don't have to appear in order.  The order of face cards, from lowest to highest, is Jack, Queen, King, Ace, which we abbreviate J, Q, K, A.  An ace can also count as 1, to complete a straight where the other cards are 2, 3, 4, and 5.  But it can't count as both a low and a high card, e.g., Q K A 2 3.