Ive flown helis for years line of sight and taught others. My class, do each step until your 100% comfortable and can maintain 5' altitude.
1. keep it nose out in front of you and fly left 15 feet then right 15 feet. keep it close and low 5' alt at most. yaw to stay nose out.
2. still keeping nose out, slowly hover in a circle around you as you turn . do this both directions
3. back to step one but now start turning in the direction of flight. Yaw on both left and right ends to slowly start facing the direction your going but turn the nose away not toward you yet.
4. hover in front of you about 15' and yaw 360.. fast but controlled. don't slam sticks. keep doing this first clockwise then counter in succession. go slower and slower.
5. same as 4 but start pausing nose in just a bit...add longer pauses till your hovering nose in longer and longer. your bale out is allows yaw nose out and catch it. (5' up.. you can disarm as well .. not something we could do with helis lol)
6. back to step one but now actually fly a small figure 8. turn away from yourself but have it flying nose in coming back to you. try small slow circles on each end as you get better.
after that its all fun.. the trick if you've never flown LOS is how backwards controls seem flying nose in. Always do these exercises slow, close and controlled until you get it in hand 100%
I use LOS for maiden and testing flights. Its good to learn.
edit: I don't know how exactly to explain this next bit but I actually put my mind in the machine, Im actually thinking as if I was in it. I don't think left or right to me, I think from the perspective of the machine. this takes practice but I believe its key and once you get it you can hover a heli upside down nose in or bring it back nose in from 100yrd away.
last but most important, you gotta fly it. don't wait and react.. stay ahead of its movement in control. if you wait to react to what it does, you'll get behind at the controls. I do very small roll pitch moves constantly, It stays in one spot hovering where I want it. ALL THE ABOVE assumes you can hover.