READ THE TOOLTIPS!
Geez. If you don't know what a game mode is, read the tooltips. Lots of useful information. "I don't know how to play this game mode," read the tooltips at the beginning.
I can't tell you how many times ive seen people blindly refuse to do anything but last hit in nexus siege.
Rabblerouser1 votesAnd then you'll probably whine at them for reading when they could be playing.
It's a new mode. People aren't used to it. There will be some confusion... EVEN IF you read the instructions. Action is the best teacher sometimes as well.
doiminat0r36001 votesThey dont show up during actual gameplay. The walls around the spawns stay up for about a minute and so do the tooltips. The tooltips dissapear when clicked or a time limit is reached.
All I'm asking, is when you spawn in, read the tips about the game so you're not completely blind. I don't care if you read them before going to lane, as long as you're in lane around when the minions colide, it's fine.
Ozag the Mighty1 votesThe point of NS is to defend as long as possible 20 mins max, or push as hard as possible when attacking.
What I have done personally is play champs that can be built offensively AND defensive even if they are OO champs. I have found that Irella and Volibear are very good with Nexus seige.
When playing defensive get the invuln, and the turret lazer for your turret, when playing attackers buy the minion buff and the cannon. The banner is good, but the buffed minions take longer to kill and deal more damage to the turrets.
Also what ever you do DO NOT let the defenders push their minions into your port point, thus powers up the obliteration cannon, and holy cow that thing hurts.
Just some words from someone who has only played 4 games and lost none of them.
doiminat0r36001 votesI don't need tips. I don't need a how to on NS. I just need a team that completely knows what they're doing. I have yet to come into a game where every person knows how to play the game mode. I have yet to have a game where there isnt a person last hitting only instead of clearing fast. I have yet to come into a game where people are not letting minions get through. I havent had a game where people say "what is the obliterator" right as they die from it.
It's not rocket science. Read the elementary level tool tips.
Ozag the Mighty1 votesYah...you'll have those KDA trolls who thinks kills win, but that's in ALL game modes.
Rabblerouser1 votesThe Obliterator's pretty much insta-death. :D The point is to force a reset for all lanes.
I like to play Jhin because he has some crazy damage to towers and is just a fun ADC to use. The issue is he's so squishy and slow... so sometimes he can't stick to the tower long enough to get past the Tower's shield (which is there to try and deter people just suiciding into towers according to the devs [this was said back in when they were testing it on Twitch on the PBE]).
But... offensively and defensively... so what you're telling me... is to be the scum of the earth. 
Ozag the Mighty1 votesOr Fiora or Irella lol