<prompt> Human: So i went to the bank to cash in a graduation check i got from my grandparents, they told me i had to upgrade from my teen checking account. one thing led to another and i had signed up for a credit card that i dont trust myself with. they said i needed it so that i could build up good credit but didnt explain very well what that meant. could someone explain how i would even go about building up good credit?Edit: Thank you all so much for the great advice. especially uTyGreeny you are absolutely right this is an example as to why i need to learn to say no more often.  <response>: A good life lesson happened here in that you were not forced into signing up for a credit card. Now that youre an adult, youll need to learn to make decisions and say no when needed, as the world is a tough place and youll face many other obstacles in life. Next time someone offers you a credit card it will happen often, politely say no thank you. Unless, of course, you want the card theyre offering. 