Elad Gil on how to ask for intros:
One of the key things you learn when building a consumer product is to make things as easy, streamlined, and friction free as possible for your users. When asking an angel, advisor, or other person to make an introduction for you, the same rule applies. The structure below saves a lot of pain & back and forth for you, as well as for the person being asked to make an introduction on your behalf.
(...)
By spending a little bit of time up front you can make life dramatically easier for the person doing you a favor / offering an introduction. It also increases the likelihood dramatically that an introduction will actually occur and yield a follow-on conversation.
Elad rips into a couple of templates (good and bad intros) to show how it should be done. As someone who has frequently both been asked to make intros, and asked others for intros, I can only agree with his approach.
Make it easy for people to help you, and they're much more likely to do so! Worth also consulting this article, this presentation from Founder-Centric, and the "Reaching Out" section of this article for additional perspective (thanks Sal for the suggestions!).
If you read this far, you should follow me on twitter here.