Take a look at your cutting and note how long the stem is before a leaf starts. The main aim in potting your cutting is to get the roots as deep in the soil as possible, as this will help them to not accidentally dry out. But also beware that if any part of a leaf or leaf petiole is touching the soil, it can potentially rot and we don’t want that. So leave any leaf part above the soil.
Fill your pot about 3/4 full with the soil mix, then gently place your cutting on top. Fill in with remaining soil until as much of the stem that needs to be is covered.
Press the soil around the plant to help hold the cutting in place. Depending on your cutting, you may need to use something to help prop the plant up until it can hold itself up.
I also like to water it straight away to keep the roots damp. Water will also help fill any gaps or holes in the soil and hold the cutting in place.