Buy a medium size plastic pot and a medium size potting soil like miracle grow potting soil or scotts potting soil.
2)Fill the pot with the potting soil, keep tapping the pot so that the soil settles down.
3)Now dig a small whole in the center of the pot, as deep as your cup.
4)Now gentally, turn your foam cup upside down and gentally tap the bottom of the cup. The whole plant will come out with the soil.
5)Carefully keep the plant in the center of pot and cover with the soil. Now genteally with your palms press the soil around the plant,the plant should be standing tall without bending. If it is bending put some more soil and press gentally.
6)Now water throughly till the water comes out of the holes from the pot.
Thats it you have successfully potted your plant.
You can keep the plant near the window where you will get indirect sunlight. This will hlep the plant grow nicely. During winter you can keep the plant near the heater (Not very close little far ) so that they dont die from cold.
Let us know if you have any more questions.
Best Wishes and Happy Gardening!!