For wedding portraits, it's generally best to use natural light, especially in the early morning or late afternoon when the light is softer and more diffuse. This can help to create a more flattering and natural look for the subjects. Avoid shooting in direct midday sun, as the harsh light can create harsh shadows and cause squinting.

If you are unable to use natural light, artificial lighting can also be used to create beautiful wedding portraits. A softbox or umbrella can be used to diffuse the light and create a more natural look, while a reflector can be used to fill in shadows and add dimension to the image.

It's also a good idea to experiment with different angles and positions relative to the light source to see what works best for each individual shot. And be sure to pay attention to the background and surrounding environment, as these can also impact the overall look and feel of the image.