Hanging out with them at the nearest bar after work is one way. But it's hardly the most professional. Here are 3 things you can do to build relationships with colleagues that will maintain your on-the-job image and promote your career growth.
1. Offer your help.
Working together on a project will offer numerous opportunities to learn about each other's personality and work style. This understanding will naturally lead to a higher functioning team.
2. Strike up a conversation in the break room.
People who dislike casual chat while they're working will be more receptive when they're off the clock. Just don't share too much: details about your love life, religious views, etc., are not appropriate for work relationships.
3. Invite them to an extracurricular activity.
Again, take your corporate culture into consideration: in some workplaces, outside socializing is the norm but in others it's not. And make sure the occasion is "safe for work": a birthday lunch for a co-worker, participation in a charitable event, a carpooling opportunity.
Your goal in making work friends is not to acquire a new BFF, but to improve the company's capabilities and get you known as the employee most likely to succeed. Use your opportunities well and these professional connections could pay off for many years to come.