How to create lights up effects

Questions
1

Hi,

I would like to create fancy effect of turning on white lights.
Lets assume easy case. Motion (wled independant) is detected, power switch is on, wled goes on and thenI would like to start effect : several blue leds go from beginning of strip to the end then from the end to the beginning all leds go white (like snake). All leds stay white until power is on.

Can you help me how to create such effect?

2

Make presets for the effects you want and then put them in a playlist and have the motion start the playlist.