Hey Oddlook, that sounds like a blast! Here's a spruced-up version of your ad for Craigslist and Reddit:
Hey everyone! I'm a 29-year-old guitarist who recently moved to the Austin area, and I'm looking to form an indie band. I'm into a laid-back vibe but passionate about making some cool rock 'n' roll. I've been playing for about 10 years and have some demos with guitar riffs and song ideas but also open creatively. It’s all about the jam for me.
I'm looking for collaborators to jam these out with. If you're interested, hit me up with your Instagram, email, or number so we can share stems and examples. I'm aiming to form a band that plays both originals and covers, and create a project worth working hard on.