Hey Elizabeths,
you will probably get a lot of responses from the regulars who know Skyline C2C like the back of their hand, but here are my impressions from my first try last year.
Adjust your start time based on the projected Palm Springs temperature the date you are heading up. I went on may 5 last year, and Palm Springs temps were in the high nineties. I Hit the trail at 4:45 and the temps were not a problem.
Water/hydration - you'll get a lot of feedback on that from the regulars, I did just fine with 4.5 liters of water but it also helped I downed a half liter of gatoraid with my coffee on the drive to the trailhead (I'm 6-2, 200 lbs, so adjust accordingly).
Finding the trail in the dark - my friend and I went up from the Ramon Rd trailhead rather than the Museum trail, and we scoped out the bottom part (half mile) the day before. The south Lykken trail from the end of Ramon is marked with paint spots and is pretty easy to follow by headlamp up pas the painted rocks where the trail meets with the museum trail to form the Skyline trail proper. to me, the trail further up the skyline ridge got indistinct and spidery at times, but you should be in daylight by them. Hiking Jim posted a really good map from So Cal Hikers I believe, so do a search for that as it is a good reference. When in doubt, keep heading uphill
Snow and ice - latest reports say the trail is clear enough up to Long Valley/tram station area, but keep checking as it might get a freak storm in the next couple weeks. A fairly decent storm hit two weeks before I went last year and there was quite a bit of snow going up to the peak from long valley. We were generally OK with just boots and poles and I did slip a couple times, so microspikes might be a good idea. In general we didn't have a problem finding trail up the flat rock area (about 5000 ft, and the start of the real climbing) and from the Long Valley area to the top it is like a freeway (even with snow there should be a well worn boot track).
Necessities - check out the Skyline quiz on this site to give you a really good idea what to need and expect. One thing that I can share is that there is a lot of spiny yucca and cactus on the lower end of the trail. Some good soul had trimmed some of it back from the trail, but I was still glad to have long pants on as my friend with shorts was nicely scratched up.
Do you have a good chance to make it? Sounds like you can based on your Colorado experience, but remember the whole C2C is about 22 miles, so getting a 20 miler done in the time before you go would help. The real thing you have to do is make it up skyline to Long Valley as everything past that is negotiable. The biggest killer on Skyline is people stopping on the way up and heading back down in the brutal heat.
Good luck, and have fun. It is a great experience if you are prepared and ready.
Ron in San Diego