It's common to simply omit the word "I" as if each sentence started with it, and to leave out determiners.
For example, instead saying
I managed the implementation of my company's revamped Web site, for which I reasearched and recommended vendors and I oversaw the copy writers and graphic designers and I edited all final content and layout
You would say:
Managed implementation of company's completed revamped Web site, including vendor research, recommendation, and selection; managed content development by copy writers and designers; served as final editor and approval authority for final content and layout.
Does that help?
[not a teacher]