No worries at all, I've actually been busy the last few days, too. :]
Seems like you've got a lot of different routes you could take.
If you like coming up with new skins, might I suggest working towards a concept artist - drawing ideas for new skins. If drawing isn't your strong suit, you could always work as a particle artist on skins or champion teams.
If you're more into creating champions, you can practice making kits for a champion (and you could always tie in concept art to come up with a visual of what your champion could look like,)
We also have a team who works on creating new game modes! You could create a doc that explains how the game mode would work, if stats would be changed, and you could note if various champions could potentially be OP on the mode.
If you have any questions about this kind of stuff, please feel free to reach out!