This lick is pretty simple for the most part. The use of a tritone sub in place of the 2 chord is what spices things up in this progression. Instead of going 1-6-2-5 we go 1-6-b6-5. The first measure is simple diatonic movement with some rhythm. In the second measure we are now playing our Ab mixolydian scale to approach the 7th of G7 which we land on beat 3. The note F. From here I added one extension in, being the b13, (Eb), then continue down the G mixo scale and resolved to the third of Cmaj7.
Enjoy!
