Whatever you want, just look for a lab with a track record of the following:
1) productivity - don't do what I did and join a lab that hadn't published since the 1990s
2) multiple undergrads going through the lab and having a good experience
3) PI that seems invested in having all levels of students in the lab (undergrad, grad, post-doc)
4) have some upper level students that can help you get your bearings
5) most importantly - a topic you're interested in! research is more fun if it interests you