Add your upline rope to the carabiner using an Anchor Hitch. Do so in such that the gate opening is pointing downward.

Clip your carabiner around the ropes of the strap.

Many riggers recommend using carabiners with locking gates. It is not wrong to use other spring gates, but having a lock adds one more layer of protection. If you have a screw-lock gate like this one…

It should be screwing downward to lock. In the climbing community, they say: “Screw down so you don’t screw up.”

Test to confirm that the gate will not open.

This is now ready to be run to the hard point.

When creating a lift system, consider running the tail under the strap. It can sometimes get slightly jammed if run through the carabiner.

Another approach to avoiding rope jams is to add a second carabiner.

Clip it into the existing carabiner...

...and run the upline through that instead. This approach also reduces friction damage to your rope.