The best way to learn good habits is to practice them deliberately. Find a section of trail that has some challenging bits but is still well within your skills. Maybe even just one tight slightly downhill turn. Then ride it over and over again while actively focusing on one or two technical aspects. For example, ride it five or six times just focused on looking out ahead of the bike. If it helps, tell yourself "look ahead. look ahead. look ahead" as you ride. Once you can do it through that section, try to remind yourself to do that one thing every time you get to a technical section on your ride. The main thing is not trying to change a whole lot of things at once. Focus on one or two things and drill them until they come naturally. Then move on to the next thing you want to fix.
If you're not sure what you need to do, for example you know your line is bad, but you don't know what the good line is, watch youtube videos or find a better rider and get them to ride at your speed (or even more slowly than you normally go) in front of you so you can see what line they take and try to match it.