First, small companies like Alda are easier to manipulate. Shorters borrow stock at one price and hope to pay the stock back by buying the stock at a lower price. The difference is their profit.

The lower the price can be manipulated down, the more money the shorter is going to make. He can have people on stock forums scaring investors into how poor the stock is (dumping), or if there was an irregularity in their filing (like Alda) in an effort to get investors to sell.

They can place hundreds of small orders at a price lower than what it is trading at and this gives people the impression their is something wrong with the company. The natural reaction is to sell your shares which lowers the stock price.

Another tactic is to place orders with several different brokers, orders that cancel one another. This creates a lot of trading activity without really moving the stock price. Volume is our friend so this tricks people into thinking there is interest in the company when really there isn't.