I have some suggestions after you have done those tutorials:
Finding a position in team that is best for you:
There are 5 positions each game, ADC (physical damage carry), APC (magic damage carry) PS: definition of carry is here, support, topliner, jungler, each of them served different purpose and being critical during some period of time.
(1) ADC: essential at later game (after 20 mins) since its items are built up. Usually go botline with supporter, require a very good farming skills (such as Last Hit, and Lining). Usually, if a game lost because of the lack of damage later than 30 mins. It is totally ADC's fault. Player's recommanded skills: good Last Hit skill (10 mins at least 120 CS (Creeps Slain) ), good lining (knowing when to haress enemy, when to fallback for jungler's gank while make CS AMAP (as much as possible)), good communication with supporter (this is very critical difference between a good player and a bad player. In addition, if ADC and supporter can't communicate well, you lose half of the lining).
(2) APC: essential at 15-30 mins, the main DPS dealer at this period. If you lose game at this period, fault maybe this role. The lining usually very aggrosive in middle since it is the shortest line and jungler are easy to gank bcz of the bushes around. Usually, you will need blue buffs from 2nd blue buff spawmed. Player's recommanded skills: good Last Hit skill & spell casting (you are not only use normal damage to CS anymore, you may use some spells to cs.), map awareness (bcz the junglers can punch your face badly), good communication with jungler (if you can force enemy recall, you get advantage, if you killed them with jungler and not die, the line is about to be yours.), knowing what to do on 15-30mins team fight.
(3) topliner: it is a essential role at time starting with first team fight, because it must be either good tank, or good DPS at later game, and not easy to die. Why? Because the top line is the long line while you only have 1 person on top. So, you must be tanky somehow. Junglers love topline, and usually topliner are OP if they get enough item, kind of like a tanker with DPS just lower than main ADC. Player's recommanded skills: good Last Hit skill, GREAT solo lining skills (as I known off, usually it is the breaking point of a team if topline winning, and since they solo, they fight quiet often and dead often too.), GREAT communication with both jungler and mid-liner (usually ADC) (Bcz you are the equally easiest to be haressed by jungler, even they can gank you. So you will need someone to protect you, who is the jungler and wards you put in bush.)
(4) jungler: it is a early role, it supposed to have not much gold in game unless it ganked well. The first 20 mins if your team lost advantages without lining problems, that must be jungler's fault. Junglers supposed to make the team gainning advantage, or at least not let opponent side gainning advantages. Player's recommanded skills: Extremely good at map awareness (so many of them such as which line used flash, buffer time, mobs spawn pattern, the posistion of enemy's jungler, line absent, etc.), great communicator (gank success or not is all based on communication). For me, it seems like the hardest role...
(5) supporter: This is a role that controls the vision on whole map, and keeps an eye on ADC. If your team lose bcz of ambush on bot half of the map at beginning, or anywhere later game, it is supporter's fault. You will never get many kills, and always bodyguard for carriers, but you will get supported by gainning money items and do not need to stand in front while team fight. While the botline's advantage is all based on you supporters.