nice guide

It's a little bit confusion about the Nomad's Medallion - sometimes it shows that you shall upgrade to Talisman of Ascension - and othertimes it's not there, and Randuins Oman is.

This guy hits it spot on

I greatly appreciate your response! But yes, this is my first guide and I do have some mess up's here.

What I was trying to say with the masteries was that I don't feel as if the masteries needed to be changed, maybe I should re-word that somehow or put in a different combination of masteries. I just never tried any other type of masteries, so it would be unfair to put them in the guide and say they work perfectly fine. I just never had any issues with the page I use.

Yes, Doran's Shield is an extremely strong start, can't disagree with that.

The Vision start is situational. The specific reason why I put the ward in that brush was because nobody goes into it, well rarely. And like you said pinks aren't much to a counter to her anymore since they're visible and they're able to take them out, which is the reason I put the pink in that specific brush. Your opinion towards it is actually a good one though, and once I play through with Evelynn without my Vision Start, I will most definitely put that in the guide! (:

With the Mobility Boots, I just added that before I read your post (:

With the Death Sentence start, I was actually going to put that in with the guide but I just started making this within 3 hours. But yes, Flay start is extremely strong over Death Sentence; but then again, there could be some nice early game plays with starting Death Sentence level one.

Thank you very much for your comment! I greatly appreciate it! I'll be sure to update my guide once I've tested your suggestions out! Thanks once again!

Hey, just wanted to share some things I noticed / disagree with (in a completely random order):

• In your mastery section, you start by stating that "Masteries are not as changeable as runes". Why not? What's wrong with a 0/21/9 alternative, for example? Also, is there no viable setup that mixes defense and utility, much like the 1/13/16 that people used a lot last season (obviously the masteries have changed since then so this exact setup no longer exists, but the idea of getting something in both trees might still work)? Statements like the one you make don't mean much when they're not backed up with proper explanations as to why they are true, basically. Personally, I use 0/21/9 every time I play Thresh and - although I'm not saying I'm 100% sure that it's better than 0/9/21 - I feel it's perfectly fine given how strong the defense tree currently is.
• Bit of a nitpick since I feel both starts are fine, but I feel like Doran's Shield start is stronger than Ancient Coin atm and should be standard. The early tankiness allows you to play extremely aggressive and win trades rather easily, which often results in getting a (significant) lead in lane.
• I'm not convinced about the "Vision Start" being the only viable option to use when playing against an Evelynn, for the simple reason that pink wards aren't as much of a counter to her anymore now that they're visible to enemies. The warding spot you suggest might indeed help your mid laner, but doesn't prevent Eve from ganking bot through tribrush or through the lane itself. Personally, I start with the same start I do in other games ( Doran's Shield + Health Potion + Stealth Ward) and don't get a pink until after my first back, which I usually place in the river brush next to bot lane. If that pink gets detected, that sucks, but there's not much to be done about it. Same goes for if she lane ganks, which that ward of course also won't detect. In the end, there's just not as much counterplay to her as there used to be and I don't feel like it's worth it to start with a subpar item start just to avoid a highly unlikely early gank that she might pull off.
• I would include Mobility Boots as an alternative to Mercury's Treads for when the enemy team doesn't have a lot of CC to worry about. Alternatively, you can also opt to make mobility boots the standard choice with mercs being the alternative that should only be bought if the enemy team has a lot of CC (this is what I personally would do, anyway).
• Sunfire Aegis is a fine item on Thresh, but its damage is much more relevant in the early and mid game (before enemies start building resistances). Buying it after a Randuin's Omen and Warmog's Armor makes little sense to me. Either get it early or don't get it all :|
• Death Sentence can be taken at level 1 when invading, but if that doesn't happen I think Flay is the better spell to take first since it makes his auto attack harass stronger. I realise you don't have a chapter that explains your skill sequence yet and maybe you were already planning to explain that the skill to take at level 1 can be different depending on the situation, but I just figured I'd mention it :P
• Finally, I've used the exact same rune page you have in your cheatsheet for a long time (armor/armor/mres/health) and I think it's fine if you're planning to start with Ancient Coin, but personally I currently prefer combining my 0/21/9 + Doran's Shield start with a more aggressive runepage (AD/armor/mres/AD). What I'm saying is it might be good to include in your 'Runes' section that deciding between the different rune pages you show can depend not only on the enemies you're facing but also on the masteries/starting items you choose. I also think the "Armor + Magic Resist" page is subpar to your standard "Health" page (as I'm pretty sure health quints make you tankier than even more armor early on and you already build a lot of armor anyway) and I would encourage you to consider removing it completely. The same goes for the "Full Armor" page, which I feel is still subpar to using a page with Health quintessences.

Despite my wall of text this looks like a pretty decent start though, good luck with the rest of the guide! :)