Most of my students have come from flyers I have handed out. The best place to hand them out is directly outside the school gates after the bell goes. Be friendly and get talking to the parents, it is so much more personable than any other way; they really appreciate it when they can see a human being behind the advert and they love being able to ask questions straight away, rather than a faceless email or text. It also gives you a chance to get first lessons booked on the spot, as you can talk about their son’s/daughter’s desires and abilities and give them the encouragement and motivation to get started immediately!
Also, bulletin boards of community centres, music shops (don’t always allow due to conflict with resident tutors), leisure centres, theatres, doctor’s surgeries, supermarkets and grocery shops etc. Hand them out on the street, take them with you when you busk, at gigs, open mics, wherever you play. Always have some business cards in your pocket.
I have used http://www.instantprint.co.uk for my flyers and business cards – they have very good prices for batches of 1000 A5 flyers, dependent upon how you laminate them. If you have photoshop or a similar program it doesn’t take long to knock up a nice looking flyer, and it probably looks better than using the standard templates online.
Get your assets together: a nice photo (or two if double-sided) of yourself or your guitar/studio. Use your website blurb and condense it down into a short concise block of text to explain your services, your contact details etc. Then it’s just a matter of arranging everything so that it looks aesthetically pleasing and catches everyone’s eyes.