We practiced this a few times in the Boeing 747, just because we could. Boeing proved over 300 passengers could be evacuated in four minutes. I twice had to order a ground evacuation of a Boeing 707 and it took nearly that much to get rid of fewer than 40.
Procedures obviously differ by aircraft and operator, our procedures are here: G450 Ground Evacuation. If you have time to plan, get the flight attendant involved. If you don't have a flight attendant, pick a passenger to do as much as you think advisable. Even if you don't think they can handle it, they need to have a plan if the two occupants up front are disabled.
For an unplanned evacuation you should have a few things memorized and you should also have a quick reference checklist easily available. In a previous aircraft I laminated the checklist and put it on the yoke. In the Gulfstream world it has become easier. They put in on the back page of the Quick Reference Handbook and made the cover clear:
Everything here is just my notes from over the years.
Note: see G450 Ground Evacuation for aircraft specific procedures.
Place medical kit, blankets, and extra flashlights in a bag and stow securely.
Cartoon: Emergency Selfie, from Chris Manno
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