Silhouette 3-column theme – 2 questions

I’m using Silhouette 3-column theme.

1. By default it shows whole post. I’d like it to show first several lines of the post with a link like “View more…” to see the whole post.

2. I’d like to add at the end of the post before comments some links like these (I believe it can be done by specific plugin(s)):
– “Explore posts in the same category” (with a link to current category).
– “Bookmark this” (with links to digg, reddit etc.).
– “Related posts” (with bulleted list of links to related posts).

How can I do it? I appreciate any help.