I was wondering about something my teacher said but I don't seem to see anywhere else...
She calls it "Sealing the cards" between uses. She pulls out the Sun and the Moon and puts them on top and bottom of the deck. she suggested I could also use the Fool and the World.
Do you feel the need to "seal the cards"?
Personally, I am a little confused how 2 specific cards can protect your deck from anything, but am really curious if others do this little ritual. I did it for a little while after she taught me, but now I don't.
That is the first time I have ever heard of that. No I have never done that or anything to try to protect my deck. I personally do not even get it why some people think that decks need protecting in the first place. I have never had anything but pure love and light from my decks. I never felt any need to protect anything. Although no one else ever touches them and I only read for others online. SO I cannot say about reading in person.
How two cards can protect the deck? They can if YOU believe they can. The more you beleive in the more they can protect. The energy of Tarot comes from inside you. The "magic" as they say is inside you. The cards are nothing more than a tool that can be used to access that and bring it out. Its all you. We seem to connect to something greater in a reading (opinions on what that is vary) but still it is us asking the question and creating the connection.
The kind of energy surrounding the experience will be the kind of energy you create by your beliefs. I personally just asked from the start that any answers I get through my cards from this point forward come only from a place of deep love and light. I just asked once, but I was serious about it. And my answers have always come from that place, without question. SO no need to protect the cards when all that touches them is love and light.
That is just one example of the energy you expect to surround the experience being fufilled. If for some reason of other your expectations included that some kind of negative energy could come and affect your cards negatively that could put you in a negative or fearful mindframe during certain aspects of reading. And it could manifest things, in the sense that we don't see the same things in the cards when expecting positive things as when expecting negative ones. Our mindset affects how we read.
IF you then told yourself that putting a Moon and a Sun at the bottom and top of the deck was protecting your deck and IF you truly beleived that and the problem was solved, You would breathe a deep sigh of relief and then feel more relaxed and optimistic. And a calmer more optimistic reader gets more positive readings than a negative worried one. (whcih is one reason why you are not supposed to do readings when you are down).
What I am trying to say I guess it that in my understanding....in one sense it is all in your head. But it can also be very real. Because your feelings will affect your readiings. Positive feelings=positive energy. Negative feelings=negative energy. Positive enegy leads to better readings.
Of course you could get the same effect by not believing your cards need protection,. But if you did, that method could work as well as anything else if you believed in it. The importnat part is your what you choose to believe.
Babs
Now it's just habit.
and your beliefs are very much what mine are. I protect my decks in good bags too and to keep them pretty as they are spiritual tools for. 
I seriously like this, I am going to start doing it..it seems fun.. I have a very dear friend and teacher she always likes to put the deck back in order after she is done, i think that's cool too but I couldn't do it..