Hint: Making an Impact in Soloqueue
Everyone always asks how they can "hard carry" for their team. Generally they get straightforward recommendations, "Play Akali, she can 1v5," "Play Tryndamere/Nasus and split push," etc. -Almost always the recommendation is "Play X champ, and give zero ****s about your team." Because that's our definition of "hard carrying" right? When your team is so incompetent that you have to win what is essentially a 1v5.
Wrong. That's not how it works. Because if your team is so incompetent that you're essentially 1v5ing, it means the other team is fed. It means you physically can't 1v5 because the enemy team is just as fed as you are, and no matter what champion you are that's not going to change. The number of times you can legitimately turn a game all by yourself in this fashion is hilariously low. So yes, it may happen once every now and then, but it's not a reason to play X champ 100% of the time.
So how do you hard carry? The answer is a lot less cut and dry, and it's why climbing in ranks is so difficult for so many people. The problem is that everyone in soloqueue tries to play their own game. They focus so hard on winning by themselves, hard enough that they can beat 2 or more people in a fight by themselves, that they lose sight of their teammates. You hard carry by lifting your teammates. That's the answer. So how do you do this?
As I said, not so cut and dry. Generally the answer is grouping and roaming earlier than the enemy team. Let me explain to you how I personally try to impact my team to give you an idea.
Note: this isn't the only answer, it's just my approach.
Top lane is my favorite location to play. Many people see it as an island, and that's because they're always trying one of those "hard carry" strategies I mentioned in the first paragraph. But what about a different approach? Rush down their tower. Kill it as fast as you can and roam. Your opponent in lane loses vision and map control with the loss of his tower. If he doesn't follow you in roams then you lift your team while he farms an empty lane. If he does follow you in roams then your team has vision and map control because you still have an outer turret and their team does not, so your roams are more likely to be successful.
Summary You don't need to get a kill in lane, or even get kills at all to carry your team. 80% of league is being in the right place at the right time. You do that by warding and roaming well and taking towers as quickly as you can. Play a champion you are comfortable with, stop worrying so much about playing those "hard carry" champions that everyone suggests, and find your own way to lift your team so that they're strong enough to win the game with you.