For the prefix, use the day you were born on. For the suffix, use the month. If you're not comfortable sharing your birthday, use a random date— today's date, holiday, etc.

Prefix:
1. Wet
2. Water
3. Stream
4. Splash
5. Wave
6. Creek
7. Fish
8. Fin
9. Minnow
10. Ripple
11. Swirl
12. Deep
13. Turtle
14. Frog
15. Toad
16. Flood
17. Carp
18. Web
19. Brook
20. Lake
21. Ocean
22. Rain
23. Drizzle
24. Droplet
25. Dew
26. Mizzle
27. Trout
28. Salmon
29. Duck
30. Mist
31. Puddle

Suffix:
January: spot
February: heart
March: cloud
April: tail
May: ripple
June: drop
July: splash
August: stream
September: leap
October: pool
November: whisker
December: storm

I'm Creeksplash.