First of all, every player that has not set his champion pool should decide which position is his priority. Most of the games you surely are going to get your position and you should have around five champions you can play at a certain level. Anything above this number is going to put you in a slight disadvantage. Why? There are 126 unique champions in league. Each one of them has a different playstyle, spellkit and passive. This is some serious amount of information to master.
2. How it should not be done
So let’s have a look at two extreme examples of a player. The first example is being a one trick pony who has mastered only one champion. It does work if you have multiple accounts and can dodge games in case your champion gets banned. Most of the time you will get your position with your champion, but those like 40-60% games you will be forced to dodge. Being a player who can play only one champion does limit you a lot in terms of being flexible and you cannot expect any team wanting you on its roster, because knowing one champion (even perfectly) is not that much ideal.
Second example of a player is master of everything… and nothing. It is exactly like this because you cannot expect that a player who has played 500 games and hasn’t played more than 20 with an unique champion to be really mechanically above average with any of those champions. This simply comes out of an idea that each game you pick a champion, you become better with it in many aspects, such as: understanding lane matchups, improving mechanical skill, finding out which comp is best for certain champion, and many more.
3. Getting to it
So… What does an ideal champion pool look like? As I said before, you should have at least five champions for your main role which you set. Then you should have around two or three champions for other roles, which gives us a number of 15 champions that you are going to pick and rotate them exactly how you need.
Your main position should contain at least one champion who is safe to pick and has synergy with almost every comp. I main support and as my universal pick, I set Nami because of her variability to work in pick comps, poke comps and dive comps. She also is not dependent on the type of AD carry, so she works out perfectly in any situation. My other four champions for support role are: Blitzcrank, Annie, Thresh and Lulu. Thresh and Blitzcrank have the same ability to snowball your lane. On the other hand, Annie and Lulu are strong teamfighting champions and what is most important: they are considered flex picks.
4. Flexes are good, flexes are friends
Having a flex pick in your champion pool is going to even tighten the number 15 into much more acceptable amount. Flex pick is a pick that can be played in more positions than just one. This gives you incredible advantage, because even if you do not get your role, you still can train that champion and keep mastering him out of your lane. Let’s have a look how exactly flexes help you. If I was a toplaner, I would most probably set my main as something that is really snowbally and can carry 1v5. Let’s say it would be Riven. My champion pool would look like this.
Toplane: Riven, Lulu, Shen, Wukong, Lissandra
Jungle: Wukong, Rengar
Midlane: Lulu, Lissandra
AD carry: Corki, Jinx
Support: Lulu, Shen
Using a flex pick at almost every position except for AD carry, you can easily tell that this pool is just one of the best possible you can use because it gives you variety of options while you still play mostly champions for your main role. Most of the time you actually do not even get your worst position, so in this case it would probably be AD carry. This champion pool contains 8 champions, is balanced and has a safe pick for your main role. What else could we have asked for, right? With a champion pool like this you will be able to play 100 games with just 8 champions and that gives you approximately 13 games with each. If a champion pool was made of 15 champions, then the number of games with each champion would go to 7. Even this difference is a disaster. And now consider your pool has even more than fifteen champions. You might have talent but talented people who set their champion pool will slowly, but surely start to outclass you.
5. Usage of my pool
I have my champion pool. What now? You should understand that laning phase is the less important part of whole game. A teamcomp is what matters the most and by seeing other people picking you should adapt your pick. Of course, this does not count for you being a firstpick. Then you can pick your safe champion anywhere you want (in this case it is Lulu and after I master Riven I would pick her anytime). Fitting your pick into a composition is absolutely crucial, because you surely had games where most lanes were in front, but your comp just did not work well and from late midgame to lategame you just got crushed. This should not happen anymore since if we still take the example of the toplane, there are strong mages who have insane teamfighting utility (Lulu and Lissandra). Having a strong tank in jungle allows you to pick those mages, Shen fills in for a tank that has global map presence with relatively safe laning. Wukong can work as a tank as well, but you want to build him more as a bruiser. Riven closes it out.
6. Creating your own pool
How do you create your own champion pool? Well, this is not a hard question as well. Before making a pool, you should really try out champions and the ones that fit you best can be added there. If you do not enjoy assassins, simply do not play them. If you love utility champions, search for CC based picks that help your team. It is just up to you and you should never be forced to pick something you are uncomfortable with, because that naturally means you are going to perform worse than normally.
While you create your pool, you can look up to statistics and browse champion guides as well. This is a good thing to do and it saves you tons of time. Why? A guide from a good player can teach you things you would otherwise have to find out by yourself, so a nice time saver is always welcome. If you are a type of a player that likes playing more than thinking, guides give you so many tips about power spikes, playstyle and exact usage of spellkit in every stage of the game.
Good luck on the Fields of justice with creating your own pool.