Although it may seem backwards, you should look to your food offerings when creating your wine list. Because wine complements the food, it is essential that the wine you chose is consistent with the established theme.
"You want to make sure that the wine list idea matches the food idea, matches the concept of your whole restaurant."
If wine is not your forte, you might want to enlist the help of someone more knowledgeable such as a wine director or sommelier. This person will be able to manage your selection and inventory so that your wine sales are making you money.
A wine director or sommelier would also be able to train your staff to understand the nuances of wine.
"One of the most common impediments to wine sales is insecurity. People don’t know what they like. They don’t know how to order. They don’t know what will go with their food. So, when the staff is more confident, they’ll sell more wine and the guests will enjoy it more."
Another thing to consider when developing a wine list is your restaurant's identity. If you are trying to establish a reputation as a wine destination, you're going to want to offer more than a red, a white, a rosé, and a sparkling wine by the glass. One thing to remember is that the more wines you have in stock, the more of a financial investment you're going to have to make.
You also need to make sure your wine and food are similarly priced.
"A standard rule-of-thumb is that the check average for dinner is what most people will spend on a bottle of wine for dinner."
Regardless of its relation to your menu price point, your wine pricing should still be such that what you are charging is greater than the wholesale price. Don't mark up the prices too much though. When people drink more wine, they typically spend more on food and have a better experience.
"If they feel like there’s nothing they want to drink in the range they want to spend, they’re going to be unhappy."
To ensure the over satisfaction of all of your guests, you should have low, middle, and high end offerings that can accommodate a variety of budgets and tastes.