I just got my first season ticket. I believe it will be on a card but i work the odd Sat so if i did want someone to have one of my tickets how does it work? . I don't want to leave my seat empty.

This is correct. You can also email box office and they will usually reply enclosing an e-ticket same day. Very easy.

I believe you can also sell your seat on twickets or something like that, but you're much better off selling for face value on here to a genuine Palace fan and avoiding transaction fees. I've always had a good experience when selling my seat on here for games I can't make.