This year, I had my first experience helping run a conference. It was small - about 80 presenters from three departments here on campus - but it still took an effort to get everything together and have it run smoothly. (It definitely gave me a new appreciation for conferences with 20,000 attendees.)
Michigan Geophysical Union (MGU) is an annual, interdepartmental conference drawing on geology, paleontology, climate, and chemistry students. It's a chance for students (grad and undergrad) to share their research in a less formal setting than big conferences, get feedback from faculty they don't see as much, and to find out what everyone is actually doing (beyond "Oh yeah, she does... mantle research?"). All in all, it's a great little experience that gives you another round of presenting practice under your belt.
The trick is getting already-busy students to attend, and to attend enthusiastically. We offered cash prizes for the top-judged posters in a few categories, included a 'lingo bingo' game, and required students who received a certain departmental grant to present a poster. As always, there was a mix of moods; some were glad to have the opportunity to practice presenting (undergrads and first-years especially) and get feedback on ongoing research, while others were annoyed that they had to spend a couple hours standing around. So what can we do next year to improve students' motivation to present at university-scale conferences?
I think that to get more first-years involved, emphasizing the fact that it's okay to present ongoing/imperfect work - and that this is a great chance to get feedback on what you're working on - is important. It's so easy during your first year to shy away from presenting opportunities because you don't have all your results yet, or aren't sure how to interpret something, or in general are just worried that it's not "there" yet. In fact, it's a perfect opportunity to get your feet wet with presenting and seek a diverse set of opinions about your work. You're doing a disservice to yourself by sitting it out.
And that doesn't just apply to younger students; on the flip side, it may be easy for a third, fourth, or fifth year to sit back and say, "Ah, I've done that already, I don't need feedback on this and I'm too busy anyway." And that's the trap of grad school, feeling like we're too busy to do anything extra or unnecessary even if it might help us in the end. Or, we participate but but in as little effort as we can manage; it's not "there," but it's passable. But even later in grad school, it's easy to settle into the routine of only talking to your advisor about your research, maybe one or two other professors occasionally - typically nothing on the scale of 3/4 of the department wandering by your poster. It's well-worth the time... and let's be honest, an excuse to take a step back from grading or pipetting!
So anyway: support your local small conference! And maybe have some beer.