Hi,
Before you set up a PPC campaign you need to have defined conversion goals. Ask yourself what action do you want people to take when they land on your website?
Also, it is important to identify the best keywords according to your defined conversion goals. Make sure you target buyer keywords and not just general keywords because you can end up losing money. That means you should target keywords such as " buy + targeted keyword" instead just "targeted keyword" because your goal is to target traffic that is looking to convert.
PPC campaign isn't something you can set up once. It requires testing and optimization. Make sure you constantly test different keywords and landing pages. That will help you determine what converts the best.
Hope this is helpful and wish you good luck!