The movies have always glamorised the importance of tells in poker. In Casino Royale, Bond and notorious villain Le Chiffre are playing a high-stakes poker tournament and Le Chiffre has made a big bet on the river. All of a sudden, his eye starts to twitch and he touches his temple. Our hero smiles knowingly, mucks his hand and watches as Le Chiffre turns over a full house to win the pot.

Real life tells aren’t quite so obvious. Most are subtle deviations from a player’s normal behaviour – known as their baseline behaviour. To be able to spot such subtle tells, you have to know how a player normally behaves – and that requires a lot of observation.

For example, it’s no good knowing that a player’s eye twitches when they have the nuts if their eye twitches all the time.