The "front" refers to the two card hand and the "back" refers to the five card hand.

No pair: Place the highest card in the back and the next two highest cards in the front.

One pair: Place the pair in back and the next two highest cards in the front.

Two pair: Play two pair in back, except split in the following situations:

One pair is 7's or greater and no ace singleton.
Pair of jacks or better and 6's or better and an ace singleton.
Pair of aces and any other pair.

Three pair: Always play highest pair in front.

Three of a kind: Always play three of a kind in back except break up three aces.

Full house: Split except with pair of 2's and an ace/king can be played in front.

Full house with three of a kind and two pairs: Play the highest pair in front.

Three of a kind twice: Always play highest pair in front.

Straights, flushes, straight flushes, and royal flushes:
Always play straight or flush in the high hand except play as a two pair if one of the following:

Any two pair and an ace singleton.
Pair of jacks and pair of 6's.
Pair of aces and any other pair.

With a six or seven card straight or flush put the highest hand possible in front while maintaining the straight or flush in back.

Play staight or flush over straight flush to improve front hand to jack or better.

Play staight or flush over royal flush to improve front hand to king or better.

Four of a kind: Play according to the rank of the four of a kind:

2 through 6: Always keep together. 7 through 10: Split unless an ace or better can be played in front. Jack through king: Split unless hand also contains a pair of 10's or higher.
Aces: Split unless a pair of 7's or higher can be played in front.

Five aces: Split unless pair of kings can be played in front.