One major difference between a winning player and a losing one is the starting hands that each of them choose to play pre-flop. Although no-limit Hold’em is a game played over multiple streets, having solid starting hand requirements gives you a large advantage over opponents who will literally play any two cards.
Position plays a major part in deciding which cards to play as you should ideally be playing very tight in early position and loosening up your standard the closer to the button you are. The reason for this is position is everything in Hold’em and the closer to the button you are, the greater your advantage is over your opponents, meaning you can play a much wider range of hands.
One of the first poker hand tips I heard that related to early position was “tight is right but tighter is righter”. The English might not be perfect but it is entirely true. When in early position you should be folding the majority of your starting hands, only playing medium pairs and raising premium hands such as QQ or better and ace-king. Being out of position for the rest of the hand, if you are called, means you need a much stronger hand to consider playing.
Once you reach the middle positions you can start to play more hands, such as all pairs, some suited connectors, suited aces and hands such as king-jack and ace-ten. If the action is folded around to you in middle position then raising the hands mentioned might be a profitable thing to do as you stand a larger chance of winning the blinds and antes as there are less people left to act, which reduces the chances of one of them having a good hand to call you with.
When you find yourself sitting in the cut-off or on the button, your range of starting hands should be quite wide. If everyone folds to you and the players in the blinds seem to be playing tight or passively then you can open with a raise with a huge range of hands, including any ace, any king, most queens, any two cards ten and above, all pairs, most suited connectors, unsuited connectors and suited one-gappers, and expect to take down the pot pre-flop. Even if you are called you have the positional advantage in the hand and could win the pot with a well-timed continuation bet on the flop.