I'd like to do research with one of a few professors within a certain group in my (American) university's Computer Science department. I'm having some trouble contacting them, but I'd like to understand what I can do, as an undergraduate student, to increase my chances of getting research with one of the profs I am interested in.
The group they are in teaches only a few undergrad classes, which, as of next semester, I have completed all of. Yet I was, through a series of extremely unfortunate class schedules, unable to be taught by any of the professors I want to research with, although next semester I will be taught by their colleagues in the same group. I talked to a couple TAs and other profs, who said to "just get better at the research topics in question", although this seems like altogether unhelpful advice given the gap between a first year undergrad and a professor's research.
There are no classes that really delve into the exact research that the professors I would like to research with do, although the class I am taking next semester covers the basics of what the group is about.
What can I do to understand what the "prerequisites" for being a research assistant to the professors in question would be (beyond just "get better")?