My current standing is Unranked, level 30.
I mainly play support, featuring Alistar, Blitzcrank, Janna, Karma, Morgana, Sona, Soraka, Thresh, Lulu, Zilean, and my personal favorite: Orianna (She's my favorite due to the fact that she has high utility [Tied with Janna, but can bring more to the team], an excellent engage/disengage, and can make any ADC tanky, which allows more sustain. [Downside: She relies too much on mana, pre-six])
I started playing league in Spring, 2014.
My rule of thumb is to not get angry at one another, through trial and error I noticed when one person (Be it enemy or friendly) is toxic/rude, a team's morality falls short, and a loss is hard to avoid. I tend to mute the other team to prevent reading/replying to said messages, and just worry more about what is going on at this moment, rather than the past.
I've had some helpful pointers through out my experiences over the past ongoing year, some through what people telling me not to do, most suggesting what I should do. After applying them, and hard practice, it's now second nature to me.
As a support I do the following:
*In the loading screen of the game, I take time to memorize each champ, possible lanes, and their spells.
.-.-.-> This allows me to let the ADC know if Mid-Lane is gankable, and what level to do so at. Along with such, I am able to keep in mind if any lanes have Teleport, so if one champ is "MIA", I'll be sure to let everyone know to play safe due to possible ganking in any lane.
*At the start of the match, I buy my gold income item (Duh), but do not buy potions, I start with a Pink Ward at level one and a Blue Trinket.
.-.-.-> Pink Ward is a given, a well placed one will last much longer than your standard wards/trinkets. Blue Trinket isn't necessarily a must, but it helps so neither myself, nor the ADC, has to "Face-Check" a bush (Sorry Garen, keep your spins to yourself).
Always rush the item SightStone, in fact it should be my first 'Back'. (Standard boots second item, then single/last upgraded gold income item)
.-.-.-> When I go to places them though I tend not to keep them in the standard Tri-Bush, River-Side, Dragon-Center locations, I prefer to give both my Mid-Laner and ADC fair due warning by placing one in enemy jungle (Eyes on their jungler allows everyone to know whether to push/shove, or freeze the lane near the tower), one our jungle river entrance closest to mid, and River-Side bush.
^^ However, just because I have a SightStone, does not mean my team does not have to ward. Vision is a team objective, not just mine, so I expect everyone to do their part
*Every ten seconds that passes through the game I should have spent 3-4 of those seconds glancing at the mini-map.
.-.-.-> Vision is key, if any lane forgets an MIA, it's my job to take command and ping for them, also allows me to keep tract of the enemy jungler (IE: Route path, where he may head next, etc etc.)
My goal out of each game is this: To ensure my team has more gold than the other.