Actually, I've moved!
However, you can do this- take Chicago Avenue west to Lincoln Avenue, then turn right onto Lincoln Avenue and head north on Lincoln to Halsted. That is a big intersection of Lincoln/Halsted/Fullerton, so be sure you're turning on the correct street! Anyway, you'll turn right and head north on Halsted to Addison, then turn left onto Addison and head about a block or two west on Addison to Wrigley Field.
Heading back, I recommend just taking Addison all the way east to the lakefront. I don't know if you can get onto the lakefront directly from Addison. If you can, there should be stairs or something that will allow you to go underground under Lake Shore Drive. If there isn't an entrance, then hang a right on inner LSD and head to Belmont (4 blocks south) and enter the lakefront bike path on Belmont. Then you can ride the lakefront back to the city and get off at Oak Street beach, which will spit you out at Michigan Avenue and Oak Street. Head west on Oak Street to your hotel.
Does that help?