Economy is for wimps.
Buy everything. Let the game tell you your team comp. Don't ever enter into a game thinking "i'm going glacials this game!" You will lose.
Just reroll reroll reroll and you get what you get. Play your items smartly. Gold 3, still getting 50+ LP for 2nd-3rd place wins. Getting almost an entire division worth of LP (70? 80?) for first place wins. Climbing steadily.
RNG is your friend, not your enemy.
Ironically, I decided to play several matches exactly the same way: farming yordels and the synergies I defined as strongest for that build. I blew gold the moment I had it to force the comp. I could consistently get 5 Yordels, make it to mid-game, stay around middle of the win ladder until I fell off hard. If I did some minor tweaking while I was in forced mode, I would have probably gotten 50/50 between 4th and 5th. As it stands, out of 6 games, I placed 2nd once and 7/8th all the other times, with 7th place being the majority of games.
I feel that experience relates a bit, and perhaps it expands on why one strat does what it does to bring you to a win, even when you're forcing that strat despite logic.
You can quite easily force a Synergy you like - and that's a decent way of climbing as well. What you can't do is force a certain Comp. That's a major difference.
Choose a handfull Champs you consider win conditions and than go for some of them. Have flexibility in the Comps around them. Focus from the very first carousel building the best items to support them.
Doesnt work always, but way more often than not.
I almost always play the same team comp. Or rather synergy. Since what I go for has several champions in a set and bonuses are for just combining 2/3 of them I can easily switch to different champ if game won't give me exactly the one I want. Forcing Yordles also works quite reliably. At worst you won't get t2 Gnar but you should almost always see one Gnar before Raptors and this comp works even with t1 units at least into top 4.
Gold1 75lp atm. Climbing steadily. But I usually spend all my gold I receive unless I am hard winning or unless I have all the champs at t2 at least and what I lack are items or XP.
That's what I've been doing in the early - mid stages of the game, with the exception of Yordles. I do not like Yordles, so that's the only thing I'll skip on. Once it hits midgame I start saving a bit to level for the higher tier drop rate while picking up upgrades for what I have started making.
