Watch the sightlines. You can make your own pointer from cardboard or plastic with a pair of scissors or you can create an opaque pointer printing with ink on a transparency film. If you are using visuals as the main part of the presentation, as I do quite often, make THEM the main part of the presentation and get yourself out of the way. You can plug an overhead projector into this unit and turn it on and off remotely. Colored film - A simple and elegant as well as cost saving suggestion is to print your slides in black on white paper and simply photocopy them onto colored transparency film.
Most photocopy machines can handle it easily.
Use overlays with overheads. Use clear film and cut out images or simply overlay them on the others that are done in colored film. Use round tables - and sit no more than 6 people per table to maximize participation and involvement. Fewer is okay, but one person is more likely to dominate conversation in smaller groups. Bigger groups become committees and people will not get involved, opting out in many cases.