(Two-part post):
I only ever sold two houses, both without using an estate agent. In the first case I simply sold to a friend, so that won't help here. However, when my father died I sold his house entirely by using my own 'DIY' approach.
The first thing I did was to make sure that I was in a good position to answer any questions about the house. I got out a tape measure and drew up plans of both floors of the house, clearly showing the key dimensions. I also took some photographs. I also made sure that I knew what the Council Tax band was for the house. From those details I put together some 'flyers', which I could send to anyone who made enquiries.
I already knew which local newspaper carried a weekly 'Property' supplement, so I placed a few ads in that. However, what actually sold the house was to cost me next to nothing. I simply produced a very simple poster on A4 white paper, with just the basic details. i.e. "FOR SALE. 3 Bedrooms. Separate garage. No chain. £xx,000. Phone: xxxxx xxxxxx". I took it to a local print shop, where I had two copies blown up to A2 size, on fluorescent paper. The house was an end property, so I was able to put one poster in the front window, and one facing onto the side road.