From this point you are encouraged to follow the examples using the testsite supplied with Typo3.

All the time, refer to TSref so you can get acquainted with it. It will be your bible when you're working with Typo3. When you're not working with Typo3, I can recommend the true God's Word instead. Much better in real life.

Use the standard testsite with a fresh template in the root of the "Startpage" branch.