You can use the funeral cards to express your love and caring for the deceased. It is better to write short and simple sentences. If you are going for generic messages, write something like, ‘forever in my thoughts’, or ‘with love and kind memories’, ‘Until we meet again’, etc. Writing something from your own words is also a good idea. Anyway, there won’t be enough space on a funeral card for you to write a really long message. But you can try to utilise the given space to write something personal about the deceased that gives you fond memories.