Its only natural that if you are a new 'seller' that listing items may be a little daunting. You'll soon get the hang of it. Remember that this site is completely free to use, so if you list an item for sale, then you realise that you made a mistake or that you don't like what you've just done, then simply delete the items and start over. You won't be penalised with charges because there are none. Correct your mistakes as early as you can though, just so that you don't mislead any potential purchasers.
Good luck, jump right in.