Can I choose what title and text appears in the extract?

I want to be able to add more descriptive titles and choose the text which appears in the extract, rather than it just picking up the first few lines of my page or post. Is this possible? I’ve seen another post which suggests using the shortcode [hupso title="my title"] but when I insert it I just get a repeat of my chosen hupso buttons.

I’m also not sure where to put it. I’ve tried inserting this shortcode at the end of my text. Is that where it should be? Obviously I don’t want it to actually appear on the page. Have I misunderstood?

I’d appreciate some help with this. Thanks.

http://wordpress.org/plugins/hupso-share-buttons-for-twitter-facebook-google/