Here are some things I do to memorize tunes; feel free to add your expertise!
**talking about memorizing the chords not the melody**
Go through and analyze the chord progression, just figuring out where it's going harmonically, labeling ii-V7-I's, and anything else that is worth noting (ex in All The Things, the C7#5 is the only chord of that quality in the song so that's something to take note of. WHOLE TONE CITY!)
Arpeggiate the chords in 4 or 8 bar sections, and loop them. Then look away from the music and do the same thing. Ok so after a section is memorized, I go onto the next 8 bar section and memorize that. Then I put the two sections together and see if I can recall all of it. I incorporate bebop scales over all the chords after the arpeggios.
then that's basically the end of it. I have to do it for at least an hour a day and it takes a while to get it really ingrained but once it's there, I never forget it!!
Please feel free to add on your practice regime and what you do to memorize tunes!