General strategies include, best options first:

• Hold any 5 Of A Kind or Royal Flush.
• Else, if you've got four 2's: keep 'em!.
• Else, if you've got three 2's:
  -hold any made 5 Of A Kind or Royal Flush
  -otherwise, keep the 2's and discard the rest.
• Else, if you've got two 2's:
  -hold any made Straight, Five Of A Kind or Royal Flush.
  -hold any 4 of a Kind.
  -hold any 4 of a Royal Flush.
  -otherwise, keep the 2's and discard the rest.
• Else, if you've got a single 2, keep any made hand EXCEPT:
  -hold four card Royal Flushes over made Straights, Flushes and Straight Flushes.
  -keep four card Straight Flushes of all types.
  -hold three card Royal Flushes .
  -pairs: with two pair, keep one, but not both.
  -hold four card Flushes.
  -hold four card Straights.
  -hold three card Straight Flushes, including gaps.
  -hold four card inside Straights.
  -hang on to two card Q or J high Straight Flushes .
  -discard two card Royal Flushes.
  -if you've come this low in the list, discard everything and try again.