Ideas for approaching this track?

Anyone have any ideas for approaching the second card track?
this is a test shot, but the real shoot will have alternating card colors (green, blue, green, blue)

The second card there is hard, since most of it is covered. What I suggest is drawing exactly the same way, but put the layer underneath the currently tracked card mask in the layer stack.
To get an optimal result, draw your layer on the second card where it is revealed the most and track backwards and forwards from that point. The previous card shape will mask out your second shape as it tracks backwards and will only use what it can see of the remaining card.
Because it’s a close action, you might want to make the mask a little tighter around the first card so you get as much detail as possible for the second.