Im a level 26 tryndamere
main, and i know all my builds. my friends always say i'm trash and make horrible decisions. most of my games i either feed and carry the other team or i get the most kills and objectives on my team but still end up dying more than most of my team. i would also like tips on how to team fight with tryndamere without getting cc'd and rendered useless.
Dude there's so much you need to learn that it's better if you don't worry too much about the nitty gritty yet, enjoy the trash phase
Sounds like you just need experience. Most people who play this game have been playing it for a very long time, and have a pretty solid understanding of fights they can and cannot win, fights they can get out of, and know when its safe to push their lane deep. All of which are especially important as Tryndamere.
One question: Do you regularly que up with friends who have been playing this for a while? If so you're probably getting put into games with people far more experienced than you and that's part of why you get destroyed every game.
Also, if you're worried about learning the nitty gritty there are plenty of youtube videos about things like map pressure, minion wave control, decision making ect. If you're getting fed but still have the most deaths in almost every game you probably should work on learning when it's appropriate to play aggressively and when you should back off.
You are playing Tryndamere wrong, Tryndamere is not good in team fights, He is good at split pushing, If you want to win game, Attract as much attention top lane, Split push and farm a lot.
Your friends are part of the "community" that you'll meet that basically shits on anybody who's not as good as them. From the Top at Tencent, to you at Level 26 Tryndamere main.
I use to watch video and techniques to find out how to best utilize my champion. After I got the hang of using champions, I began experimenting. Not just "experimenting" like some person trying to take Karthus Jungle for the first time ever because he saw a streamer do it. I was abusing S2 Eve with 1600 crit damage at level 13, using S5 Graves to deliver ludicrous bang, and going Darius Support. All of these champions have had changes to drastically reduce their ability to function in these ways.
Karthus Jungle still somewhat works, but if you get someone to Counter-Jungle you like Shaco, Kha Zix, or Twitch then you're kind of screwed.
The reason you're trash is that you have very little experience. You will be decent after a couple years of spamming thousands of ranked games.
Try getting tiamat instead of shyv. Shyv's been pretty shitty after the nerf and it's a delayed powerspike. The build Boxer Pete ran was 
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. Blood Thirster isn't a good item on Tryn either, Death's Dance is better because the passive gives you more time to use your R.
To teamfight with him you have to wait for the enemy team to expend their CC on somebody else before going in, otherwise you won't even get near anybody do actually do damage and will just be forced to waste your ult while standing frozen in place.
the trick is, you don't. you split push a lane pretty much all game, because you deal lots of AD and can take turrets quickly. you can easily 1v2, or optionally run because not many people are fast enough to catch up to you, which is your job as a splitpusher
