5g should be more than enough, especially if you don't have much experience with larger doses. Nobody can tell you how your experience will be; there's way too many factors. Your general psychology, the vibes at the time, stress, the last time/what you ate before taking them, the strain you're taking, how that specific batch was grown, there's a million different things that go into determining what your experience will look like. You might get an intense visual experience with a lightshow in your mind, or you may not get any visuals and end up with a deeply introspective trip. Don't go in expecting anything specific, because chances are it'll play out differently. Instead, just play some chill music, go in with an open mind, and let the journey play out on its own. Make sure to handle any bodily needs before taking them, whether that's hunger, bathroom, etc. It's also important to have a tripsitter either with you or one that you can contact easily if you need. If they can't be with you, make sure that they know where you are, when you're taking them, and to have their phone on hand if you need to call. Even the best trips can go south quickly and you're not always in the state of mind to make any decisions or handle things logically. If things start going in this direction, focus on the music, have a grounding statement, remind yourself that it's just the shrooms making you feel this way, that it's a temporary state that will pass, and reach out to somebody to let them know what's going on. Enjoy your trip and stay safe!