If you structurally choose to play better hands than your opponents then you will already have a great advantage over them. Especially if you are just starting out in Texas hold'em then good starting hand selection will keep you out of trouble after the flop.
The little 's' stands for 'suited' and the 'o' for 'unsuited' or 'of suit'. Good starting hands are those hands which either don't need to hit the flop (like big pairs) or often make the best hand when they do hit the flop. These hands make the best possible flushes and make top pairs with very strong second cards ('kickers').
The bad starting hands do not offer the possibility to hit a straight or flush with both cards; they are unconnected and unsuited. They will hit low pairs or top pairs with bad kickers and will lose you chips when your opponent hits the same pair with a better kicker. Don't play these hands. They will get you in trouble more often than not.
If you have the button or are close to the right of the dealer then you will be very likely to act last after the flop. This gives you an informational advantage over your opponents: you can see what they do before you have to act. Try to take advantage of this by playing more hands 'in position' then 'out of position'; play most of your hands when you are (close to the right of) the dealer.
Putting a lot of your chips in the pot with just a single pair rarely is a good idea. If you have a middle pair or a top pair with a weak kicker and are facing strong bets from your opponent then you are usually beat. Fold, keep an eye on this opponent and win your chips back when you are the one with the stronger hand and he or she isn't able to let go of the weaker hand like you did.
Big pairs like aces, kings and queens are great hands to be putting a lot of chips in the pot with unless you see the flop with many opponents. Then the chance of someone hitting a better hand than you will be bigger. Just raise your big pairs pre-flop to fold out the weaker hands that might flop a lucky two pair otherwise and to give yourself a higher chance of winning the hand.
If you are aggressive, meaning that you bet and raise a lot instead of just calling, then you give your opponent the option to fold to your bets. By taking initiative and being aggressive you therefore give yourself an extra possibility of winning the hand. Don't overdo it though; you don't want to be aggressive with a hand that would deserve a fold instead.
What this means is that if you make a hand with both your hole cards it will be more concealed for your opponents and the chance of your hand being second best is generally smaller. Don't draw to a one card straight, because it will be obvious to other players when there are four cards to a straight on the board. You will either win very little, or lose a lot to the player that uses both his hole cards to make a better straight.
Having a rough idea of the odds of hitting your draws and of how to calculate pot odds is very important in order to play winning poker. Although for the first time poker player pot odds is not a subject to directly dive into (it takes some time to learn), it surely will be rewarding to follow this pot odds guide when you decide to play poker more often.
As obvious as it may sound, the smallest stack of you and your opponent will be the limit as to what you can win in no-limit games. If this stack is very small, it might not be rewarding enough to chase certain draws as you won't be able to win enough when you hit to make up for the times you miss and lose. Your 'implied odds' aren't high enough.