Not on SWOL, but Google ALPA Jumpseat Finder and you'll find listing procedures for all relevant airlines.

The rules are pretty simple:
1. Check the ALPA guide to see how to list for each carrier, as all have different procedures. If you're J/S'ing on Skywest you just show at the gate and request to be listed for the J/S from the gate agent. On all airlines, if there are seats in back, you'll sit in the back. If it's full in back, and nobody is ahead of you in J/S priority, and the airplanes' weight & balance will allow it, you can sit in the actual.

Note that CRJ-200s are notorious for being weight-limited (it's a CG thing, not a total weight thing) when they're flying a short leg and have alternate fuel onboard. In that case it's not uncommon for us not to be able to legally take a jumpseater up front. The -700 and -900 are much less prone to this issue.

2. Follow the listed dress code: uniform or business casual. No jeans, no sneakers, no T-shirts, etc.

3. Once you've listed (either at the gate, or online, or on the phone, depending on which airline you're J/S'ing on), show up to the gate no less than 20 mins prior and check in with the gate agent. Gifts of chocolate are sometimes well-advised, especially at busy times when you're just another problem the gate agent has to solve. The gate agent will need to see your badge and ID so he/she can verify you're in CASS, and he/she will print a J/S request form or boarding pass for you. Every airline's procedures vary, and every gate agent's procedures will vary, so just go with the flow.

5. Ensure you have all your credentials (pilot cert, medical cert, employee ID, passport, and the J/S pass the gate agent will give you) ready to show the CA. Wait till everyone else boards, then board the airplane, poke your head into the flight deck, introduce yourself, and politely ask the CA if you can have a ride. Offer to show him your paperwork (some guys won't glance at it, others will examine it closely). In my experience, if I'm jumpseating on my own airline, most captains just see my badge and jumpseat card, and they're happy with that. On offline carriers, some CA's will ask to see all of my credentials. Some just care about the J/S card because it shows you're in CASS.

6. Be polite to everyone, stay out of the way, and remember you're officially an additional crewmember, so don't do stuff like talk/text on your cellphone during taxi, etc. If you're in back, don't order alcoholic drinks.

That's about it, really...