Queen needs life and mana. Although armor doesn't hurt, you only want to get it from the 2 typical places if you don't want to gimp your build. Nimoth, and later Groffling if the game goes on that long.
Typically items get picked in this order to play QoT, but this is always situational depending on map, money, your opponent's DG + build and how long it takes you to get kicked out of your lane.
Monk + Botf
Unbreakable
Scaled Helm
Banded
Siege
Vlemish or Plenor (depends on map)
Minotaurs
Nimoth
Upgrade scaled helm to Plenor or Vlemish
Upgrade minions
Options depending on the game
Banded -> Gladiator Gloves -> Gloves of Fell-Darkur
Banded -> Hauberk -> Groffling
Explanations
Unbreakable comes before banded and scaled because you need life and mana, and it is more efficent then those 2 items, and you will usually have 2K+ gold before returning to base because QoT is very strong early game
Scaled Helm is important for the mana regen, it is nice if you can get it at the same time as unbreakable. (ie: lane well)
Banded is important for more cheap life
Then you get siege to harass towers while laneing
Then you get your 1st big helm to be able to start using spikes (having siege already in play is usually nice, because the 1st time you pop open and spike, DGs are going to get hurt fast by surprise, so every point of damage counts for a possible kill)
Then you want minotaurs to distract towers when you are spiking, they are nice to get at the same time as your 1st big helm
Then you want Nimoth for life/armor as you begin to push or defend battles that are further distances form safety and high powered damage skills start to fly around.
Then you upgrade your small helm to more mana becase spikes IV + other skills is expensive.
Then you decide if you want to focus on damage output or survivability depending on the game.
