Include research experiences. Especially if something came out of the project.
Include extensive paid experiences (so not you worked 2 weekends and got paid $500, but you spent a semester or longer working, or a recurrent summer job, etc). And include them if they were important to you. I worked as a phlebotomist for 1.5 years before med school and I keep that on my CV not only to explain the long gap,between college and med school, but also to illustrate that I know systems outside of the typical physician experiences.
Everything else... decide what matters to you. If you’re interested in teaching, include the TAing you did. If you’re interested in working in underserved communities, include long term communit service opportunities. If you’re interested in pediatrics, include extensive experiences with kids (not the one weekend you volunteered for something).