I find myself performing John Guastaferro's Out of the Blue more often than not, but at the end, I'm left with 4 blue cards which do not fit in with the rest of the red deck. What's the best way to change them "back" to red?

I have a himber wallet from Marvin's Magic back when I was a young'un but that introduces an unnecessary prop.

Take a look at Paul Gordons Four Card Fooler.
Vanishing inc has this as a five dollar download. Great trick.

That sounds intriguing, fonda57. Is the trick examinable at the end? Bob

If you put them in your pocket.

Could always do a simple switch, under a cardbox or something. Or you could control them to the bottom of the deck and palm them out.

Thanks for this suggestion. However, the ending is rather dirty and the faces of the queens cannot be shown. I've now adopted Mathieu Bich's Back Twist. It too doesn't end clean, but at least I'm able to show the backs and faces. It also allows me to solely focus on the back color changes (via the Asher Twist) and without the unneeded "twisting" effect when each queen turns face down.

I'm in no way saying Paul Gordon's effect is bad. Far from it. It's a genius idea and will be a fooler - a lot of thought had gone into it and is a great twisting trick. It just isn't suitable for my own personal purpose.

Check out Peter Pellikaan. He has some incredible tricks where faces and backs change. https://www.vanishingincmagic.com/magician/Peter-Pellikaan/
I can't remember what the trick is called but you can't go wrong with anything that he produces. They are all quick effects and aren't hard to do.

Maybe a face up 4 by 4 change. There’s a book on the subject by Karl Fulves called Packet Switch. Hope to be helpful with your search
Bye!

If you use a topit you should check out Carl Cloutier, he has an instant change of 4 cards.

Great idea, but I only wear T-Shirts.

As you see there are many ways you can change cards, Paul Gordon has ways Peter Pellikaan has ways,If its packet tricks then these guys by far have the greatest Packet Tricks out.& yes you will learn to switch packets n cards like no other.