Dual front line safety systems won't make the kite flag out instantly when the safety is released, as opposed to 5th line or single line safety systems, which make the kite flag instantly.

The simple way to help the kite flag on the beach once the safety is released is to release a bit of tension in the front lines by walking a few quick steps forward. This is well shown in this video at the 4:00 minutes mark:



For self landing I would recommend you try the method shown starting at the 2:45 mark in the video below. The main difference between this and most other methods is the safety aspect meaning you won't get dragged by the kite if you fail to land it.