How do you play yours at the lower levels? I have issues in the first dungeon. I get seen too easily and my daggers just don't cut it...

How have you built yours?

With difficulty, until you get up a few levels.

By first dungeon do you mean Bleak Falls Barrow? Basically sneak around a corner, shoot the draugr, then turn around and sneak the F away til ur not detected, rinse and repeat. It took me forever to finish and the last boss handed me my manhood in a sack multiple times. My assassin's got all of the perks in Sneak, 5/5 in the first perk in 1handed, almost all the perks in Archery, and most of the perks in Pickpocket. You're gonna get your butt handed to you until you can get some of the sneak perks that increase crit damage and make it harder to be detected.

I found myself leveling sneak and archery together until i got to about 50-60 sneak i had enough -Detection + the backstab perks and from that point forward it was just me sneaking up and instagibbing people.

First few levels are difficult because everyone sees you. Stick to bow, for start. And what will help you a lot is if you take Sven (or his competitor) with you as a follower.

Take a melee follower.

sneak + archer = never getting hit the whole game

What builds have you gone for?

What builds are you all using?

My "Evil Ranger" wanders in a mix of Dark brotherhood , Enchanted Glass armor, and a pair of 20% bow damage gloves. I carry a Fire bow, the Nightingale bow and a Soul trap bow for keeping them all fed. I only lightly enchant my weapons and armor... More fun to hit the guy with 2 arrows in his eyesockets than One arrow that leaves a scalded, magma filled trench for a mile behind him.

As you start slowing time with the bow, it gets more "fun" (threading arrows under your NPC ally's armpit like Odysseus threading the Axe handles) but a lot of the play until your Sneak is high is "harass and withdraw"

I've crouch-walked most of Skyrim, sneak is 100 now and Life is good... But with the DB gear ( and gauntlets for 1 hand crits) I've been fairly good at up close kills of singles since the 60's.

Mehrune's Razor is a great weapon, I usually dual wield it with a soul-trap weapon. ( at least until the Blade of Woe)

A good assasin is part rogue, part mage. Nocturnal grants you luck, but a little skill in the arcane doesn't hurt. Use your alteration spells until your sneak and one-handed weapons is high enough to take out a room full of guards without being noticed.

I made a build entirely without magic. In Riverwood just chop wood for money and pay Faendal to train you in archery; you'll have a good basis upon which to take enemies out undetected.

(there's also an exploit so you don't spend any money, but the 'legit' way still stands).

If your assassin is a kahjit you're really powerful at low levels unarmed because of claws.

Fun Fact # 1: A good assassin is one who does the job he was hired for, and does it without collateral damage.

Fun Fact # 2: You can use any character build in this game to be an assassin. (e.g.: Orc with two-handed sword and underwear? Assassin. Mage with Fire Bolt and Fancy Clothes? Assassin. Altmer with an axe and Steel Plate? Assassin)

Are you using a stealth + dagger build? If so, you need to throw archery into the mix if you plan on doing any kind of dungeon delving or basically anything outside of the Dark Brotherhood quest line. I favor stealth characters. I use archery and I always have a follower (they often draw the enemies so you can stick to the shadows). At low levels it takes a few arrows to put down targets but, with range and assistance, it can be done.

Daggers will be useless until you take the Assassin's Blade perk in the Stealth tree.