Technical writing is different from writing for marketing materials, news, or journals. You need to follow the rules or guidelines for technical writing. Normally, large organizations have their own corporate writing style guide. If your company does not have its own writing style guide, you can refer to the Microsoft Manual of Style for Technical Publications (MSTP). For the general writing guidelines other than those specific for technical writing, refer to the Chicago Manual of Style or The Elements of Style. (Sometimes, technical writers are like detectives as they both need to dig out the information/resources they need. I believe you can find more information about technical writing styles on the web. :p)
Want to read more? Check out these writing style guides:
- ASD Simplified Technical English (STE)
- IBM Style Guide: Conventions for Writers and Editors
- Sun Microsystems: Read Me First! A Style Guide for the Computer Industry
- Apple Publications Style Guide
- Google Android Writing Style