1. Wank a lot over the course of the week.
2. Gather the semen in some box or glass and put it into the fridge.
3. Put some wooden stick into the box/glass
4. When the semen is frozen. hold the frozen semen with the stick.
Grats, you just made semen ice.
You can add any kind of taste to the ice-semen, similar to normal icecream.