Train, you COULD try increasing the worth of the bonus, but the real issue with the large bonuses is that it takes quite a few turns to secure one, especially if you are playing with a warlords type setting.
To separate the borders, heres a quick tutorial: (image 4 and on)
http://imgur.com/a/h1fnR#4. Also, as a hint, when doing offset, use ctrl+J instead of ctrl+). It gives you the ability to offset to a specific distance, which is extremely useful.
Good luck!