To start with:

- If there are an even number of cards dealt, select that the proctor should start.

If there are an odd number of cards dealt, select that Sam starts.

Then you need to select a prediction card of your own, which is placed in the envelope at bottom right.

Whoever goes first, two cards are selected and slanted. If it is Sam who goes first -- select any two cards OTHER THAN the prediction card you placed in the envelope.

If one of the cards the proctor chooses is the card you selected for the envelope, then click on the OTHER slanted card. You need to keep that predicted card in the game!

Just keep the predicted card unclicked and in the game up until the end -- it needs to be the last one remaining.