Maybe this is caused by an eye allergy. Try a cool compress before you go to bed, I guess it may work to some extent. And you had better pay more attention to your life habits. Such as eating food without so much salt, take low-carbohydrate meals, and never drink water before you go to bed. For the moment, you might as well try a cool compress coz it can help reduce the puffiness. Well, besides those reasons, you can also consider if they are caused by an eye infection or an eye inflammation. If this is the main reason, I can only suggest you to go to an eye doctor as soon as possible.
If you just get swell eyes in the morning, it is probably caused by drinking too much water before you go to bed. Or you may not get good rest last night. Here i know that using cold compress can help reduce swelling eyes. Maybe you can have a try. If you always get swelling eyes, it may caused by inflammation, if so, you'd better consult a doctor for some prescribed medicine to help the eyes.