Just don't talk, because most the time it leads to an argument.
1.) Understanding why you are losing.
2.) Knowing your ability's your ally's skills, and its important to note what jungler your team has as well as what champions they are playing.
3.) Counter warding is important to make sure your jungler isn't seen when going in this is the act of making sure vision wards are down and the enemy has no vision in the very least tri-bush at all times so defensive/aggressive plays can be sneak in from behind as well as denying ward in first bush by tower if doing that type of play.
4.) Having a useless support, Siona Support, Annie Support, there are better depending on how your lane is losing for example having a braum, can be useless compared to having a Sona, or Leona, the problem is that (You need to be able to execute a skill/combo within 1 second or less if that.) if you can't do this you need serious training I mean all players in general because this is something that can determine a fight lost or won or enemy escaping etc.
5.) Understanding what skills your enemy has up, do they have flash, ignite, what ultimate they have up etc, there are dozens of examples and lots of lines of text of why I could explain this is super important.
6.) knowing the position of the enemy jungler at the time your jungler helps.
7.) Knowing who your jungler is what they can actually do for example a (Master YI) can go all in) ignore slows for example which means that if a braum is there he pretty much is useless to his mate if half HP and over extended, meanwhile if your (Support is Leona) / Sona and plays it correctly and you follow all this plus enemy is half HP you have a chance of winning the fight, otherwise you need to know what to do when you have other champions like "Sejuani" she is like playing a support, but she isn't going to be able to dive the best tactic around this would be to go something like Katarina, and just go bot lane and combo them at the same time 4 bot lane roam = win every time, heck you can even do little dives / resets with kat or akali if you team knows what they are doing a lot of times I would dive with 
at 6 get 2-3 kills and die because my mate doesn't understand that if they stayed within turret range I could E out on to them and live but enemy gets 300 free gold because of that.
But honestly good luck explaining all this to someone in bronze its just never going to win without a big argument / fight your better off putting together a pre-made team of 4-5 players even 3 players is better than 0 who actually know what they are doing.
A really good jungler especially in bronze that personally works a lot for me unless the enemy gets massively ahead, or takes something like Volibear / UDYR (Akali) and (LeeSin) Lee-sin because he can easily just rekt people early/mid game, even counter jungle pretty damn hard I might actually try a new tactic of taking (Teleport / Smite) as a jungler for the purpose of getting to a losing lane faster that is about to die, the problem though they don't always ward so good luck explaining that one too, because half the time people would argue how useless teleport is on a Jungler, or why taking Smite, or Exhaust top is useless.
And personally I disagree with not helping a losing lane, (If your team and players actually have some brains) its better to group or do something early than later but if not then there isn't much a JG can do themselves especially if they have to sit down and type an essay out for the 2 bot players for example to understand anything.
