I know this might be obvious but I watched some youtube videos and noticed how some people were able to sneak attack with a dagger or a bow without alerting near by A.I, I know that high sneak skill help and I already maxed out mine but I still get detected while assassinating people even though others don't see me do it. Also, is there a way to shoot at someone without making them rushing toward you?

As long as I am hidden and the other people aren't in the same room I never get detected :/

I don't have problem in rooms but let's say I need to kill someone in town so I crouch and I become hidden and I kill a guy with the other npcs facing away from me so it would make sense that they don't detect what I did but they tend to detect it even when they are facing away from me...

Doing it in broad daylight significantly increases your chances of being detected. If you wanted to kill someone roaming around in town, best to do it at night.

Sources: Experience

yea that was frustrating. I sniped nazeem while hiding behind a house and clearly no one was watching, and yet i get 5 guards + the whole town on my back and no bounty.

I feel your pain, especially if your sneak is already maxed out, killing in day light shouldn't be a problem...

_{Nah... I don't think it'd be no problem. Killing in daylight, in town with people about... even if you're a stealth god doesn't mean the person whose throat your cutting isn't gonna scream bloody murder so to speak...
I usually follow my target until I get them alone someplace.... down a dark ally or even into their own home... (><)}

As long as I don't assassinate in broad daylight and/or in public view I hardly ever get detected straight away. And with proper sneak skill it's rare for me to be detected straight away in broad daylight as well.

What does happen is that someone might detect the assassination, and starts looking for the culprit. But as long as I avoid everyone and make my way out sneaking nobody knows it was me.

Using a bit magic can help. Like a Muffle spell or Muffle enchantment on a pair of boots, and items that Fortify Sneak which are usually quite easy to find if you search all the shops.
Its better to sneak in light armor or just clothes rather than heavy armor as well.

I have seen people placing buckets on the heads of NPCs.

Has anybody yet tried to place a bucket on their own head? Who knows and it might work. The game has got bugs and if you cannot see them, maybe they cannot see you either.

Tried, and failed.

In towns if your not in their house you will almost always get detected. Wait until night and break in and kill them.

I find I won't get detected or raise alarm at all when killing in town as long as everyone is far enough away from the target when you make the kill. Always kill at night. They have to be a good distance away and it also helps if the target is standing in a dark spot. Timing is everything. If all else fails try casting Invisibility or drinking an invisibility potion right before and after the kill.

It's almost impossible to use sneaking properly unless you're playing with an xbox controller.

I'm gonna call BS on that. I have no problems whatsoever sneaking on my PS3. It works exactly like it's supposed to.

What I meant was, it's impossible to sneak properly on the PC using a keyboard and mouse.

Sneaking on the PS3 is obviously just as effective as sneaking on the xbox.

I highly recommend the Nostromo N52TE for PC sneakers. Puts all those useful keys right where you want them.

I just turn into a werewolf, sprint into town, kill the target, and sprint out. The NPCs don't recognize your identity when you're wolfed out, so no bounty.

I had some problems with sneaking and killing when using a bow. As soon as the arrow takes flight, they seem to hear the sound from the string and moves/stands up towards the sound, thus making me miss my shot. And that do just svck!

Daggers make no sound. Other weapons alert the NPCs when they're drawn or used. That's something most people don't take into account.

NPCs usually shout something when you stab them to death, which means that nearby NPCs will be alerted to their sound. To be entirely safe, your best bet would be to kill people in their homes, or make sure you're a distance away from other NPCs.

I find the trick with bows is distance, the further from the target the less likely they will hear it but if someone else is close by they still see the target fall look around but cause your far enough away they cannot see you while in sneak. Daggers are silent while moving in sneak,but if you sneak up on your target and stand behind them you can take out your sword(only) and it's just as effective as long as your not moving with your sword.Muffle helps,and anything that ups your sneak skill is a benefit, usually I hunt from dusk till dawn and most time I try to stay as high and as far from my targets as I can( I use a bow more than a dagger/sword) and I have only ever been spotted once or twice and that was cause I was overzealous and wasn't watching my environment.Also, try not to pick the body right away, wait till no one else is around and then pick the body.

never had any problem there either, can you please elaborate on why would it make a diference?

There is a Perk for that.

Slightly off topic, I think we get 50% of the threads saying Sneak is OP, and the other 50% saying is not effective.

This tells me that Sneak is just about right.

You can't control how fast you walk with the keyboard.