The only equipment you'll need to be a litter picker is a constant supply of bin bags, and perhaps a pick-up-stick.
You could also offer your services to the owners of famous landmarks such as churches and mansions. Picnic areas too, many of which are owned by the local council, become soiled with the wrappings of sweets and sandwiches, spoiling the scenery and putting off others.
Your local council may be interested in your litter picker services to help keep their highways clean, and you could approach local event organisers e.g. fêtes, pop concerts, outdoor theatres etc.