Especially at young companies, the contract-to-hire strategy is wildly popular, and for good reason. It can be
Make sure you're encouraging your co-workers, including those not on the contractor's team, to introduce themselves and make them feel welcome. It's a nasty habit, but some team members might not want to bother chatting with someone who might only be around a week or two. Push your team to go out of their way in this regard, because at this point, everyone in your company is a recruiter.
Make sure your contractor has all the tools he or she needs to be successful. Whether it's multiple monitors, wireless accessories, or other workstation needs, it can serve to make your contractor feel valued and as though they're being taken seriously. If you're concerned about having to splash the cash, odds are you're going to need this equipment down the line anyway.
Similarly, leaving contractors off email threads, company chat clients, or other meetings will alienate the talent. As long as no sensitive information is being discussed, loop them in as much as possible.
Try to coordinate with team leads to ensure your contractor is helping out with interesting projects. Obviously, they shouldn't be a part of your Skunkworks Projects, but if they feel stimulated right off the bat, they'll be far more likely to want to stick around. Put them on data entry detail and watch them leave after week 1.
What other strategies do you use to convert contractors? Leave a comment or tweet @EnteloRob!