Hi i'm silver 4 recently climbed out of bronze, playing alone like u, after like 1000 games in bronze, i have learned some things, i main top like u, but also play other lanes. Here's my advice:
1.-Disable the all chat, i have been punished by giving up or feeling the need to tell others how bad they are doing (flaming) and stuff.
Believe me in our elos it doesn't matter what ur team has to say and the all chat is just to tilt the rival.
So go into options, disable the all chat, and when u start the match type /ignore all, and just focus on playing.
2.-Watch the map, always buy a control ward when u have 75 gold to spare, and watch the map, sometimes i get the tunnel vision and got ganked but i try to watch the map whenever i can.
3.-Update ur trinket! Never forget to do this, if u are playing top and don't want to facecheck the bush just get the farsight alteration, or if u are playing vs teemo, get the sweeping lens when he reach lvl 6 and oracle alteration when he is lvl 9
4.-Focus on farm, not on trades, in the laning phase many people tends to be so aggresive, and yeah sometimes they will win the trade with a big combo, (for example pantheon with thunderlord's and ignite deals a lot of dmg) only trade if u know for sure u will win the trade. But the farm is way more important. If u don't know if u will win the trade, then just farm.
5.-Use pings to tell ur team someone is missing (or other things) even if him is not on ur lane.
6.-Get a small pool of champs to play, this way u will have like 4 or 5 champs for choice, avoidings the ban problems and getting countered.
7.-Take the right runes and masterys, if u have doubts, u can check some pages like mobafire.
8.-Based on ur experiencie learn who champs counters others, i mean we aren't pros but for example if i going vs gnar, i won't pick gangplank. That kind of stuff will give u the advantage in ur lane. if u have problems with some champ, search on reddit, how u can deal with him.
9.-As i said before, focus on farm, but also objectives, don't overstay in the map, if u took one turret down but u only can see one rival in the map, time to go, remember if the enemy is not in sight, can be anywhere
10.-Try to keep the herald, dragon and baron warded, even if ur supp don't have wards, do it urself or tell others to do it if u don't have wards at the moment.
11.-As Darkdemon said, try to watch ur replays to learn which mistakes u did.
Sorry for my bad english, is not my native language, hope it can helps.