1. Know what kind of game you are playing. This is a war game, not a peaceful game. If war isn't what you signed up for, then you're simply playing the wrong game.
2. Be skeptical. There are alot of people in this game who say they know what they are doing or can offer guides on how to play. Anyone can say anything. But you need to ask yourself when you listen to these people talk whether what they are saying makes sense and if what they are saying offers plainly visible benefits for fighting. Overly complex explanations for why a seemingly bad idea is supposedly good idea usually means that it's a bad idea coming from a bad player.
3. Be humble. If you're new to this game, recognize this fact and don't expect to be some kind of out of the blue phenom. Best thing you can probably do is try to find yourself a mentor who DOES play well, and listen to what he says. When he says "offensive start is the way to go" don't give him any yeah-buts. I never understand why or how so many new players put worlds of faith into the bad teacher's plans eventually paying off, but so often seem to dismiss as wrong advice when it comes from good players.
4. Don't plan, try, or want to conquer the world. This kinda goes along with #3. On dozens of servers and about 100 worlds, some of them being open for several years, there has only been once where it's happened that a tribe has conquered the entire world. Focus on what's in front of you. Dominate your 15x15, make a good first conquer, things like that. In all honesty, new players should not view their first world as where they will accomplish very much. All you really need to do on this world to make it a success is learn, so that the next time you'll be even better.
5. Have a sense of urgency. This game proceeds slower than your typical computer game or video game, so alot of new players get sucked into thinking they have all the time in the world to eventually start making troops, or wait until later to worry about one day coming under attack. You need to learn how to start strong. And then you need to learn how to continue strong. Often bad players will offer you instructions where they talk about "eventually" this will be to your advantage. If it takes two months for a plan to pay off, you'll be dead before you get there.
6. Play other strategy games. There are two particularly I can recommend, being chess and poker. Both of those games are similar to tribalwars in certain ways. Chess is a war game with an assortment of pieces that have unique characteristics, where you have to learn when to attack, where to attack, and weigh sacrifices against rewards, all while developing and altering strategic and tactical conditions. In poker, you are playing against many people, all of which may be potential allies or enemies at different times, where you have to learn to read and gauge a person, while weighing how much an investment costs you, how much it will give you in return. These are skills that can go a long way in tribalwars. But the most important thing to understand about these three games is that chess and poker both have a fairly simple set of straightforward rules, but actually learning how to play and play well takes time and involvement. And the exact same thing is true for tribalwars.
7. When in doubt, TROOPS! In chess, everything happens from what you do with your pieces. In poker, everything happens from what you do with your chips. In tribalwars, everything happens from what you do with your troops. Your troops give you fighting strength, and you've probably already heard a million times that troops win wars, not points. But let's move beyond that worn out line. Troops give you resources. Troops indirectly give you points (through farming, which allows you to build your village). Troops give you dominance in your area even when you aren't attacking other people (from outfarming opponents, catting down barbs to protect them from being nobled by weak players or to at least make for poor villages when weak players noble them anyway). Troops bring you respect from others and can mean the difference between a strong tribe being willing to accept you as a member and teach you how to play, or being stuck with no other option than crappy tribes that are disorganized and lead you over a cliff by teaching you all the wrong things. Just remember that everything you are doing should be based on the goal of getting more troops, protecting your troops, or using your troops to your maximum gain. When someone offers you such and such guide, you should ask yourself "how will this give me the most possible troops?" If you can't find a good answer, then you shouldn't listen.
8. Be all that you can be. Sorry if it sounds trite to quote an old US Army motto. But noob tribes often neglect individual ability thinking that working together is enough by itself. Teamwork is important, very important as a matter of fact. But a team of very good players working together will always defeat a team of so-so players working together. You will never become a better player if you don't strive to be a better player.