First of all, be sure you know what you are looking for in staff. Sure, a buxom young female in a tight uniform may bring in the customers, but it is sexist and illegal, and besides what if the only thing she can do is look good. Waste of time and space - you would then need to employ someone else who can do the work. Also do you want to hire students? Some are fantastic, but then again, you can get the other extreme. Plus they need time off to study and sit for exams - can you afford to hire someone who will fill in for them while they are away? Do not be restricted by age - our best worker is a lady in her mid 50s. But then again, our worst worker is another lady in her 50s - and we've got staff from 15 years of age and onwards. Once you have decided, what you want......
Advertise - whether with an employment agency (which means that you don't have much work to do with screening!) or in newspapers (local and major), internet, by posting signs in the window or on the light pole out the front of the business or even an ad in the local primary school newsletter!
I have tried all of the above and the most successful has been the local paper.
I try not to give to much information over the phone, because then not only do they have all the information they need, but often (you'd be surprised how often) do not turn up for the interview without even calling to let us know!
When I interview prospective staff, I tell them of the details of the job including the ups and the downs and then ask if they are still interested. I ask for details of their previous experience with a time line. Be on the look out for those who over-inflate or exaggerate their experiences. You don't want the person who said to me that she had experiences working in all aspects of a cafe and it turns out to be as a dishwasher 30 years ago, when we wanted an assistant chef!
Ask them for examples when things have gone bad, as well as when things have gone well and how they coped with those situations and/or ramifications.
Ask them what they think their previous employer/s will say about them (you will get some very interesting replies!) and follow through with a call to their references, with an ear out for hesitations while the referee fabricates untruths.
Put in place a trial period - 3 weeks, 3 months (but not longer than that), it is up to you. If you feel that a person does not have what it takes despite your efforts to train or talk to them, then do not feel guilty to keep them. You (and your other staff) will be very unhappy if you do.
Most of all, I trust my gut instincts - more often than not, it is right. I've learned not to hire someone who didn't feel right just because we were desperate for staff. We have wasted a lot of time, effort, and money on people who just did not fit in, or were not experienced, or left soon after training, or in one case, a thief.