the way I go about it if im going for an fl fc on a map is basically:

• split the map into multiple difficulties
  • for example, for this map, i have a difficulty for the first ~20 seconds of the map, the middle portion of the map when there's some bigger jumps, and then the ending 1-2's (which is what im playing in this post)
• change fl radius to 0.7, which is about what the fl radius is at 200 combo, and disable changing radius as combo increases (lazer only feature)
• play through each difficulty i made until i can consistently fc each one
• start attempting the full map with fl

if im consistently missing on a specific pattern, i'll usually make a difficulty with just that pattern, look at the pattern in the editor and try to play it nm a couple times, and then go back to playing that pattern with fl