Some general vital things, a few I stole from a website to jog my memory

Wear headphones and turn them all the way up, sound is vital; from determining where gunshots are coming from, to footsteps around you.

First 10 mins can be a bit jumpy in terms of connection. After that it generally stabilizes.

Try to predict where the center of the zone will be so you can camp out more so constantly spending it running to try not to die

headshots are vital

aim the camera straight down while you're free falling to hit the ground quicker (your chute will auto deploy). Constantly tap and let go of W if you want to go further whilst free falling

In the pre-game, take off your shoes. Barefoot running is the same speed as running with shoes, but you're noticeably quieter on most surfaces.

Remember to toggle your rate of fire with the B key (one shot for when you're outside, semi/auto with close quarters)

Avoid big towns if you want to actually be in the top 20

All doors in the game start closed. If a door is open, someone's been there. If you leave a door open, you're telling the world you've been there too. Therefore, get in the habit of shutting doors behind you unless you're rushed.

Always clear buildings (unless you're very rushed) before looting

After the beginning the game, pistols are almost completely pointless

Avoid bridges like the plague if you need to cross one to get into the safe zone

Hold your breath while aiming with 'Shift'

Don't go for a kill unless you're 100% certain you can win that fight. The moment you shoot, break a window, take off in a vehicle, etc, you're putting a beacon up across the map showing what area you're in. Your best bet is to avoid combat if necessary. Remember, it's a survival game first.

http://www.eurogamer.net/articles/2018-01-19-pubg-tips-tricks-guide-battlegrounds-4415

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