read throughly the requirements eg: SRS

The initial stage of testing starts with the study phase..
i.e. Understanding the scope of the project.
In this phase you clear your assumptions and questions with 
dev.This is very important.
Note: Not only the project knowledge but the other 3rd 
party products involved(for ex. your product may interact 
with MS Sharepoint or exchange Server so that knowledge is 
also necessary).

2.After understanding the scope of the project you need to 
write test Plan.

3. In parallel develop Test outline ->test scenarios ->test 
cases.

4.Review the Test Plan and Test Cases (Peer review) and do 
the rework if any.

5. Freeze the Test Plan and Test Cases. If you have any 
repository like TD or QC then upload your Test Cases.

6. Map your Test Cases with Requirements you alredy fed in 
the repository.

7. Prepare the Test Environment Setup and Data Setup.

8. Prepare your documents need from testing like 
Trackers,etc..,

9. Start Testing.

Testing initiation : during this testing phase project
manager  will prepares  project level document. here he
concentrates on below factors.
  
             1. type of project
             2. scope and involves
             3. risk analysis