1. Prepare brief but specific chronology of the most important events.
Prepare a chronlogical list of the important events, such as: date of hire, date of termination, your starting and more recent position with the employer, your most recent monthly wages, and dates of any positive events (good reviews, promotions, etc..) and negative events (whether fair or unfair) that include any warnings, suspensions, demotions, discriminatory or retaliatory comments and actions by the employer etc.
Instead of using adjectives that don't really say much, such as "hostile", "abusive" and "unfair", quote specific statements and describe specific actions of the employer that you believe were illegal.
Don't elaboriate on information that's not relevant. For instance, if you weren't terminated for poor performance, there is no need to discuss at length how good of a worker you were.
Every case can be summarized in a one-page chronological list, and the stronger your case is, the easier it is to summarize it.
2. Gather and submit all the important documents.
These documents include termination letter, any documents that reflect positive on your employmet (promotions, award letters, good performance reviews), and any negative information, whether fair or unfair, (bad performance reviews, counseling letters, warning letters for whatever reason, notice of demotion or suspension, investigations, etc...).
Make sure to include all the important e-mails that you sent or received that might suggest discrimination on the part of the employer or their lack of action in response to your complaints about any unlawful conduct.
If your case is about disability discrimination, include your main medical documents reflecting your diagnosis and limitations and any proof that you put your employer on notice of your disability and the need for accommodations, as well as the employer's response, if any.
Be ready to present your case on the phone through a brief statement.
Good attorneys are also busy attorneys. You want to present the gist of your case through a brief statement that would capture their attention. There is no need to tell the lawyer that you case is very complicated, as it doesn't really say anything.
Here is one example of presenting the case briefly but effectively:
"Hello. I have been working for company x fo 12 years and only received good reviews. I injured my back on the job, was placed on disability for 2 weeks, released with accommodations, and as soon as I returned, I got my first bad review and was terminated a few days later for stealing, which I have never done. I tried to present my side of the story but no one wanted to listen. My most recent salary was $ per month."