Need help adjusting my strut height.

[Bullyboy]

basically you just need to lift the bottom perch to move the round snap ring.
I have heard different methods of supporting the bottom perch (Metal/wood bracket) while the car was jacked up . Then lower the car and the perch lifts up.
If you choose to do this, be very careful . The spring is still under pressure and could do some serious damage to you if it slips.