How to be a Fortnite Pro

1 Crouch when shooting.
Crouching reduces the size of your crosshair allowing you to shoot exactly where you want. Use this when you have an Assault Rifle and there is space between you and your opponent.

2 Always get the higher ground.
Getting the high ground allows you to control the action, make it more difficult to get shot at, shoot unexpecting players from above and get that all important head shot. Build yourself a ramp to get the higher ground or stay on top of mountains or the roofs of buildings.

3 Learn to build.
Many players run away or fire back when someone shoots at them. This is wrong and will result in you losing your precious health and probably losing. Instead, quickly surround yourself with walls to give you cover and place a ramp to give you the high ground. If you're bad at building go to Wailing Woods and start breaking down trees(don't completely break them down as it will reveal your location) and start practicing making walls and ramps as fast as you can. But make sure you have a gun and you're keeping an eye on the storm.

4 Attack everyone
Hear shooting? Don't run away from it run to it! The only way you are going to get really good at this game is by playing it. And no. Hiding in bushes and in your trap infested houses doesn't count as playing. It's hiding(camping) and eventhough you might make it down to the final 5 your chances of winning are slim. Look for fights and don't be scared to die. It is just a game after all.

5 Watch the pros play
There are a whole host of talented people who play this game and watching how they play will serve as an example of how you should be trying to play. Watch Ninja and Myth but I especially recommend Daequan and Sypher PK as these guys will give you tutorials and help you find out what you're doing wrong. You can find these guys on YouTube and Twitch.

Season 5 is almost upon us and these tips should help you succeed in this new season.
I hope these tips help and feel free to drop an upvote to give yourself some competition.

Peace.