I just learned 3s this season, and what i did was before hitting the jump, I twisted my upper body around until I could see the tip of my ski on the other side. Then I just repeated that movement off teh jump and landed 'em! It is important to pop really hard too, of the jump, because that brings your legs up closer to your body and gives you more airtime as well. Also, once you land them good, just do 3s off everything.
as in any sport u gotta practice and ull get more consistent
I find it helps me spot the landing, becasue I am looking really far over my shoulder. The problem for me is when I do left side 3s the same way it makes me drop my shoulder so i go off axis a little and its harder to land.