Hey, fellow silver/gold here. In low elo like we are, it is much better to pick a couple champs for each role you might play and learn them very well. It doesn't matter if they are meta or not - just that YOU know them well and enjoy playing them. If you get to diamond/plat+ then you might want to consider learning how to adjust to the new meta as patches change what is meta. But if you are lower than that, learning how to play your champ effectively in all sorts of matchups is best.
Besides finding a few champs 2-3 for each role you play (ex: jg, mid, sup or top, sup etc.) you should find a good streamer/youtuber or two to watch. Not just some high elo player, but someone who actually explains WHAT they are doing and WHY they are doing it. Guides can help, but there is something else about actually seeing it unfold as you hear about it.
So if you like azir, know that you outscale many other midlaners. I know this sounds stupid, but actually it helps a lot if you keep reminding yourself of this. Why? It means you don't have to overcommit to WINNING laning phase. Going even or losing only slightly vs someone you outscale is a win. If you can get bullied by a certain opponent, try to exploit their overconfidence. Ex: baiting them into a tower dive where they die or at best trade kills or... baiting them into the arms of your jungler or roaming support. Just focus on farming in lane. Don't be afraid to back when you are low hp - even if you will miss some cs and xp - because if you stay, you still miss most of it AND end up feeding away a free kill. It's painfully hard to do, but you can do it.
Learn your matchups. Ex: are you against a talon? Watch out for his fabled lvl 2 all-in. Where did their jungler start and where are they most likely at right now? Will they be more likely to gank early (ex: lee, elise) or just farm for 6 (ex: sej, noc, kha). What combo's will your opponent use on you in lane? How can you best position against that to minimize their damage via the combo while maximizing your own? What items can you best build? Do you need mr rush? Can you punish them for lack of waveclear by shoving in early and backing - negating the harass they got on you? Should you let them push you in and farm by tower and try to freeze lane on your side of map?
What does their team comp look like and what does yours look like? Are they heavy in tanks and cc? Lux is probably a bad choice since she's immobile and unable to kill tanks or poke them low enough before they can hard engage and delete her with their base damage and any followup from enemy carries. Similarly, kat and zed would be bad picks here. Starting to get the picture?
Don't just build recommended items. Look at both team comps, how well allies and enemies are doing, and adjust your build accordingly. Ex: Fed enemy toplaner who rushed mr? If they are going to try to get in your face, you might want voidstaff 2nd/3rd item instead of whatever you normally build. Or no enemy mr and all squishy or able to be ignored due to lack of meaningful damage and cc? Pure damage or flat pen would probably be a better choice.
Finally, let your jungler and teammates know in champ select or upon first spawn on fountain that you are likely to get bullied early and might need a bit of attention but that you outscale (if it's true).
High Damage - can be assassin or long range, impacting through mostly high damage (
Utility/Niche - act through unique skills, capability, or a lot of cc (
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