The prime mistake Newbie's make is to put their website name into the Anchor Text. Unless your website contains your keywords this is a waste of a perfectly good link. Remember that Google puts a very big importance on those Anchor texts and they should always use your keywords.

The second mistake is trying to put every single keyword into your anchor text and give that to everyone. There are two mistakes with this technique.
1.) Google assigns weight to each word in anchor text so if there are a lot of filler words (common in long sentences), they will "dilute" your target words

2.) You should vary your text throughout your links. That is, change it every 20 or so. This just makes sense. If your links were placed naturally, there would never be 300 links all with the EXACT same anchor text.

So with all that in mind here is an example:

You sell Blue Widgets in England and want to rank first for "Cheap Blue Widgets in England"
Your anchor text could be varied between the following:
Cheap Widgets
Blue Widgets
Widgets in England
Cheap Blue Widgets

Hopefully this helps you start an effective campaign.