Hi there,
I never had trouble finding private students - placing ads in newsagents and on supermarket noticeboards, or in cafés, at the university noticeboard in the language department and that kind of thing.
If you are good word of mouth goes a long way.
Plus for children see if the local school will cooperate and hand out a flyer from you - sometimes they will do that - there's no postage as teachers give the form out to children. That can work if you are offering to give the lessons at the school as extra support - it can seem that the school have more to offer to parents.
Since doing my private tutoring around the world I created a book of one to one games and video so any private tutors viewing this who would like extra ideas please feel free to check out
www.homeenglishteacher.com
All the best
Shelley