How can I increase sales in my pizza place?

Social Media: interacting with your customers through social media such as a Facebook page it's a great way to naturally promote your product. Show pictures of your location, your staff, your pizzas, etc, and make it easy and friendly to encourage your actual and new customers to visit your place. Plus you can run promotions or contests, asking questions or proposing special tasks and giving a special price for the winners.

Take advantage of the different seasons and run special promotions for special events or holidays, promoting a specific product or giving discounts to groups of people.

Other than that, try to be part of the community. Know your customers and build a relationship with them, show that you care about your local area and sponsor or support different local events such as sports events, providing of free small pizzas to the participants for example.