When adding a card to your Collection, you can choose to copy the card from a Ladder database card (or another card in your Collection already).
1) Click on the card's profile.
2) Click the Options Menu (three vertical dots) on the top right.
3) Choose "Copy Card." This will open a new window.
4) In the new window, you can update the information from the original card to the new details you want to update (ex. grade/variation/player).
5) Upload your picture, if you have one.
6) Don't forget to hit Add at the bottom of the window.