Convert a Template to a Website

I have a wordpress site that I've implemented which works about 95% out of the box. There are a few things I'd like to tweak, which I don't believe the theme itself easily allows without getting into the css, which is not my strong suit. 1) I would like a custom footer that allows a horizontal nav bar and a working twitter widget. 2) I would like a custom header that gives me the ability to place my logo flush left with a nav bar ALSO flush left directly under the logo. 3) On each portfolio page, which can be found by clicking on any one of my work projects, I would like the embedded vimeo video to take up only 12 columns instead of spreading to nearly the entire width of the screen. The only way to do this in the theme currently is to pad out the sides. I don't want to go that route. These changes NEED to be responsive so it works on a mobile device. My temporary website is [login to view URL] I am currently using the Crush theme if you would like to investigate. Thank you so much. Look forward to the help.