Then what you need to do is go to a fishing tackle store and speak with them (you can also get a license at most fishing shops).
I mainly fished at Chatfield and on the Platte, but occasionally went up to Cheeseman lake. There are tons of little ponds around, and you can drown worms there all you want. Just take a rod, some hooks and some worms and go throw them in the lake.
Is the lake stocked or is it just the natural fish population? If it’s stocked, it won’t really matter what you toss in the water…they’ll probably eat dirty socks.
If you’re planning to release, I wouldn’t use worms. There is a slightly smaller chance of failure, but a lot of the lake fish in Colorado will swallow the worms very deeply; taking them out usually involves yanking out some serious fish guts and then all you have is a bloody fish to hold–one that you probably wouldn’t want to eat anyway, and will certainly die if you throw back. Maybe take some worms as a back-up if the lures aren’t working.
Depending on the lake, a couple of spinning lures would probably do the trick. As a bonus, they sort of keep you entertained as you’re reeling 'em in.