For mounting a giraffe I prefer to do a climbing mount. I’m not sure if that is what it is called, but that is the motion of it.
Anyways, I mount with my right foot, so I position the right pedal straight down, in lined with the frame pretty much.
Hold onto the seat with both hands, and put your left foot on the tire, right between the frame, so if you put any weight on it, the tire will not roll forwards.
Now with your left foot firmly on the tire, step up and bring your right foot to the pedal, as soon as it is on the pedal, bring your left foot to the other pedal and your body over the seat.
All that should happen in the matter of seconds. Then ride away.
If you mount with your left foot, its the same procedure, just switch what I typed above. Left foot becomes right, you get it.
There is also the rolling mount. Walk, job, whatever pace you want with your uni in front of you. I like to go at a fast walking speed for this. Like I said before, I mount with my right foot, so as the right pedal is coming up towards me, I do a little hop to get my foot on there, and put my weight straight down on it, this cause my body to fling up onto the uni, and the unicycle to pedal backwards bringing me right on top of it, then I either ride backwards, hop and do a 180, idle for a little, or just ride straight forwards.
Watch a video with giraffe mounting in and practice a lot.