Using a menstrual cup for beginners can be tricky and does take some effort but in the end it's worth it. First of all wash your hands and wash the cup well, we prefer sanitizing the cup before and after by boiling it in water.
Fold the cup into a pinch fold which is the most common and easier. There are different folds you can try. Sitting is the best position but you can also try it standing with one leg on a chair.
Relax and take a deep breath and insert the cup. Insert it till halfway and release the suction and push it up slowly till you don't see or feel the stem. It's normal to feel uncomfortable for the first few minutes but later it will be fine. For the first two days empty the cup every 6 hours if you have heavy periods, for the rest of the days you can use it for 10 to 12 hours.