A company information session or recruiting presentation is typically a job seeker's first in-person interaction with a new company, so making a great first impression is key. Even more important than what one says, future employers and recruiters will take note of a perspective employee's clothing well before he is even in speaking distance.
Because looking sharp is key, men should pay careful attention to their appearance and make sure that they are wearing proper clothing. For most situations like this, business casual is the proper attire. A pair of nice slacks, a buttoned down shirt and nice shoes are all that is required. For industries that are more formal, a sport coat or jacket may be appropriate.
When in doubt, it is better to be dressed more formal than less
Remember to also bring a nice looking notebook and pen
Plain traditional colors are a safe bet unless you know the culture of the company