Ranked advice, Test Play everyone.

Even if your going to be a dedicated 1 trick its entirely worthwhile to take the time to play every champion. Use free week, test things out in normals or bots. Knowing first hand what a kit can do, when a power spike happens, and how champions work is only to your benefit. Hell if your not hurting for BE try rentals thou that system really needs some QOL changes to fit into the BE system better. (I am still pushing for a champion shard rental rework. Keep the shard in inventory for discount or have it give BE on expiring, its got potential to help newer players but currently its rather subpar for f2p players wanting to test champions)

Now this is from my personal experience and thus has some bias but doing this helped me end season 3 in gold instead of silver. Also quick cast W indicators or quick cast spells because double tap default is terribad. Some champs need 1 or the other learn what works for you and increase your reaction speed.

Glhf yall.