Keep Moving
It is important that you keep moving, all of the time. If you remain still you make yourself an easy target. The best strategy as a new player is to move slowly and stay at the back of the pack. Avoid running off on your own while you are still learning the game as doing so will only expose you and get you destroyed.
Work as a Team
World of Warships is a strategic game and you will have the most success if you stay with your team and follow the leader. Communicate with your team when a situation develops so you know what your role is
Ship Positioning
Movement and positioning of your ship is very important, always be aware which way you face your enemies when you encounter them. Ideally you want to face your side towards your enemy so you have more firepower options available than if you face them head on. Keep in mind that your secondary guns do not have as much range.
Cannons
The key to sinking enemy ships when targeting them with your guns is to look where it's going, not where it is and make the adjustment accordingly. You need to get good at predicting where they will be by the time your cannons reach them. This is going to be different for all ships and cannon types and will also be more difficult the farther away they are.
Evasion
When maneuvering to avoid the enemy remember that your ship cannot reverse as fast as it can go forwards which makes moving forward your best option. Regardless how you decide to avoid the enemy you need to always be aware where the enemies are at all times and never find yourself with them on both sides of your ship.
Cover
Use the environment to your advantage. Islands and rock formations can provide good cover from enemy fire. A good strategy is to stay near a rock and emerge and reverse back near it as necessary to fire on enemies and avoid fire yourself.
Beginners Guide
The video below is a guide for the inexperienced and new player to the game showing you how to play each class of ship, which ammo type to load on each ship type, equipping your ship and getting the most out of it before and during the battle.
0:00 - Port and equipping your ship
6:52 - Battleships
16:32 - Destroyers
28:00 - Cruisers
34:00 - Carrier