As we get older, we realize more and more how important our girlfriends are. 

And in order to help us keep those friendships close, Head and Shoulders has launched the Good Girlfriend Guide, an e-mail manual filled with advice on “head-scratching behaviors from beauty and fashion faux pas to relationship hang-ups.”

All the proceeds are being donated to Women’s Empowerment, a non-profit organization that supports women in need to help them find jobs, homes, and live a healthy lifestyle.

Alyson Hannigan, star of “How I Met Your Mother,” is supporting this worthy cause as their girlfriend ambassador.

Back in June, she encouraged ladies to post their best girlfriend tips on the Head and Shoulders Facebook Fan page. The guide features some of these stories and suggestions, along with celebrity style and skincare tips. 

“It’s a great manual of great advice that girlfriends give each other,” the actress told PEOPLE. “It’s nice to know you’re not alone in your boat.”

It’s been a busy month for Hannigan. Besides the book release, she just announced that she’s expecting her second child with husband Alexis Denisof. The couple already has a two-year-old daughter, Satyana.

The Good Girlfriend Guide can be purchased on the Barnes and Noble/NOOK website until June 2012. The e-manual costs less than a dollar and can be read on your iPhone, iPad, or Android, if you download the free NOOK app.