You're going for the outs 101 to 130 with 3 darts for each out.
Scoring
5p - You finished the score within three darts
3p - Missed a finishing double with 1 dart
1p - Left the out with a finishing double

Example 3 points

Your out is 101, you hit T19 and 12 with your first two darts and miss the D16 with your third dart = 3 points.

Example 1 point

Your out is 101, you hit S19, S20 and D15 which leaves D16 = 1 point