OP Spider Lady

Introduction

Before even playing Broodmother, or even using this guide, please acknowledge two things: There is a reason Broodmother has one of the lowest winrates in the game, and that is because she is extremely easy to counter.
Sentry wards are listed as an optional buy because if you are in a solo lane and they are sentry warding your webs, you can use your sentries to destroy theirs and either cripple their vision or force them to buy/ask for more wards.

Also, try not to play Brood if there is another heavy stealth hero on your team like Riki, Nyx Assassin or Clinkz, because generally a good team will buy a gem to counter these heroes, and whether they meant to or not, inadvertently counter you somewhat.

Pros / Cons

Pros:

Strong hero most of the game
Extremely hard to outlane
Amazing pusher
Can have high rune control when played mid

Easy to counter
Spiderlings weak to aoe
No hard CC
Unreliable slow

Early Game

I think Broodmother is best as a solo, seeing as if you keep a lot of spiderlings up and web up your lane, you can easily take someone else if not two other people.

As Broodmother, try to know exactly which lane you need to be in and get there as fast as possible. If there are lane switches they'll have to conform to you, because you need to get to lane to web up before creeps get to lane.

Try to get your basi ring/soul ring soon for the mana regen, as being able to web up and cast spiderlings is a huge benefit early in the game.

Once you're around level 4, you should be okay in your lane, as your Q will be good harass and good farming, if you're keeping spiderlings alive you can easily fight enemies, and if you take a lot of harass while farming your webs and a tango will have you back to full health more quickly than most heroes.

Always remember that if they enemy is sentry warding your webs, purchasing your own sentries can be an easy fix, considering you'll still be even on gold.

Try to get to level 9 or 10 soon, then raise a great army of spiderlings, and push the enemy tower. If you can push the enemy out of lane, then not even a fortify will deter you from pushing that tower. Once you've pushed the tower, there are a few options.

Mid-Game/Post-Laning Phase

Now you have a few options as to what you can do.

If your team didn't have a jungler, you could easily go into the jungle and start farming.

You could web down the river to make ganking both fast and effective, while also gaining a bit of rune control

If you're playing Brood as a hard carry, continue to farm your lane and push out or kill the enemy laner.

Finally, you can play Brood as a strict pusher, roaming to other lanes to create another spiderling army and crush another tower.

Any of these routes are completely viable, and can be done with generally the same build and all benefit your team in different ways, the only part left is choosing what your team needs the most.

As for myself I usually play her as either the hard carry or the pusher, because I feel these are what she excels at the most. Note that Broodmother is pretty item dependant once the early game is over with and her spiderlings don't hurt heroes very much anymore. You'll need to farm up that Orchid Malevolence soon whether you're playing carry or not because regardless of your position you always need to keep the mana up to use at least two of your abilities, one of them preferably being your ult.

Late Game

Late game, all I can really say is to teamfight smart. If you can, lay down a web or two where you think the next teamfight will be so you'll have a bit of extra regen and you can have a chance to escape when you really need it.

Broodmother can be instrumental in winning a game when played correctly, so go out and knock down some towers.