Read the room
If you have your TV in a large room, try repositioning your furniture to hit an optimal distance from the screen. This will depend on your screen size and the resolution you’re watching content in. With a 32–inch screen, aim for a minimum of 4ft; if you’re rocking a 65–inch panel, then you’ll want somewhere around 8ft at 1080p, or 7ft at 4K. Having your TV at eye level is optimal. When using a projector, recommended distances do somewhat go out of the window, but try to make it comfortable.
Think about your audio setup too; positioning yourself as close to the center of your surround setup makes a huge difference. Subwoofer position is not important, as low frequencies are not positional, but rear speakers need to be pointing in the right direction. Sitting facing a soundbar, rather than having its audio bounce around the room gives a more convincing stereo effect.
A home movies chair could make a big difference to your experience. Firms such as theaterseatstore.com offer a range of indulgent options (popcorn not included).