The first step is to determine who you’re selling to. Are you looking for new customers or broadening the horizons with your current customers? Answer this question before starting your sales approach.
Once you have defined the direction you want to go, consider your resources. What equipment do you have in order to do the personalization? Do you have the staff to handle the new work and to keep items updated in your store? This information may determine which areas of your business you want to or can grow.
The key is to start with items in the area you want to expand and watch how they are received. Introduce items that will not disrupt your current business. Step into something you are comfortable with and your existing customers won’t balk at. You may need to switch things up a few times to get the response you hope for.