if your Clek is REAR-facing, follow this video 100%.

If your Clek is FORWARD-facing, you will need to have the car seat uninstalled from your vehicle (as the straps are against the back of the vehicle seat when the seat is forward-facing) AND you should not find yourself having to unclip and reclip the tether to it's storage hook - as you should ALWAYS use the tether on EVERY forward-facing car seat.