Play it safe, don't overspend
If you are just starting out, look to get a secured credit card. These are credit cards where you must deposit funds to them before you can spend. Its a way of making sure you don't get in over your head. So if you put $500 on the card, that is all you can spend on it. No debt, since you have a hard limit that you have already paid for.
Using this type of card and simply putting more money on it month after month is an excellent way to either build (if you are starting out) or rebuild (if you have bad credit already) your credit score.
Don't have more than 1 card until you have developed good habits and are disciplined enough to not overspend
Even if you don't plan on using a credit card, its not a bad idea to get one early in life and place a single re-curring charge on it, like your cell phone bill. Paying this off on time, every month will give you a good credit score later in life.
Do not use more than 20% of available credit at a time. Pay it off a couple times a month, keep the balance used low and your credit score will rise pretty quick
START EARLY - Credit is something that should be built from a young age. Most banks offer student credit cards designed solely for this purpose. They have low limits so you don't get in over your head but they make it easy to build your credit.
Credit score can also be affected by non-credit cards.
Get utilities in your name (power, water, land-line, etc. Sorry cell phones don't count). Car loans or small personal loans from the bank are also a good way to increase your credit.
Keep your credit card safe. It's not a bad idea to have a separate credit card just for online use. Keep the balance on this card low (say a couple hundred). Use that card only for online purchases. If you get hacked, at least it has a low balance and you can recover from that fairly quick without damaging your main card.
The main way to build your credit score is TO BE RESPONSIBLE. Do not overspend, do not go wild thinking you don't have to pay for it right now. ALWAYS pay the FULL balance BEFORE the due date. If you can't afford to pay the credit card off in full each month, you have overspent
Follow this tips and you're credit score will be healthy in no time
To increase ones credit score, he must prove to be thrustworthy with paying off his debts and generally make good financial decisions.
Let's look into what the kind of actions one can take to increase their thrustworthiness and increase their credit score.