I started Iron 2 and I am up to Silver 1 in about 2 1/2 days give or take.
General advice is don't just toss items on anything, I wouldn't combine anything early unless you are sure it's something that can be put on a different champ if need be. Often I'll sit on components till I have an idea of what I want to build with what I have (comp included).
This gives you a lot more flexibility to play around with since if you built something like a Titantic Hydra Early for your Graves but now all you are getting Mid / Late are Casters and you haven't been able to upgrade that Same Graves from 2 star to 3 star then that Titantic Hydra was basically wasted; So if you are building a Titantic Hydra (just as a example) you need to have an idea of how it can transition into your mid game comp.
2nd thing is don't fight the RNG, this is something that takes awhile to really get use to; for example I just got 1st in a Game with Shapeshifters..I have NEVER ran Shapeshifters before let alone did I actually WANT to run it; but the game gave me 3 Elise early..AND THEN it gave me another 2..And then A bunch of Nidalee as well after I had grabbed that Elise...I said well ok looks like I'm gonna try and run a Shapeshifter comp!
Early on it sucked, I think I lost 13 straight or something?? But My elise was Full Evolved and I tossed a RFC on her as well as a Titantic Hydra AND a Red Buff! Then I got some Sorcerers which Included Twisted Fate for quicker Shifts
AND THEN I Got ASOL AND Shyvana literally RNG magic made the ASOL lv 2 after 1 Round and Shyvana almost just as Quickly..Never played with a Dragon Sub Theme before either.
Point is I went into the round fully expecting nothing, don't expect certain comps or items ever, instead have an idea of your champs that you may enjoy that are splashable example Pyke and TF are 2 that imo are splashable in almost any comp regardless of whether it's mid/early or Late, so even if I get a Elise sorta comp I know that if I put priority in getting a TF or Pyke (even in Carousel) that will really help my chances, same thing with Lulu as well, these 3 imo are staples and can be plugged into almost anything to shore it up.
Also i don't know if you have a TFT Item List Cheat sheet
But this really helps me to make decisions on what i may want based on the component(s) i have.
Last thing is to not lock into 1 comp, especially the later the game goes, it COULD be possible that you start off with Nobles and holy smokes you just get so luck RNG that all of them end up getting upgraded to Lv 3 and have the exact items they need to be great all by the end game...It's possible...But it's also highly unlikely and generally speaking you should be willing to dump large portions of champs at the drop of a dime if i'm being frank..
For example, if you are getting dumpstered with some sort of Glacial comp, your Ashe is still lv 1, you have no items on her; you are getting slaughtered over and over by the same teams and you are on a healthy losing streak and the matches are not close then hopefully you were paying attention to what the RNG has been trying to hand you. Always prepare, if you notice these picks like Cho'gath and Kennen coming up and it's 2 at a Time, even if they don't fit into your comp currently you should be getting them anyways just incase another comes.
Or Yordles for example is something that constantly pops, all sorts of yordles all the time..If I'm running something like Glacials or idk maybe Void something or whateva, and I see yordles coming up, I will slowly (not that slow tho) start plucking them up because the fact is they are all strong even on their own without the perk; a lv 2 Veigar or Kennen or Lulu has a lot of merit in my opinion and if you have some items to toss on them as well then hey you know what they can splash and play in your current comp to cover whatever you need.
Things like that; Now I may think those 3 Yordles are borderline Staple picks (Lulu is for sure a Staple imo) and maybe someone else doesn't