Frontier Theme Sticky Question

I have been getting my business back up and running, after taking my site down several years ago due to a non compete clause from an old employer. After several days with cruddy themes, I found Frontier. Hallelujah! It has everything, so far, that I need. On a scale of 1 to 10 I comprehend site design at about a five. Anyway I tried to lookup changing the Sticky Color in the FAQ’s and I found the Asteroid instructions. I tried to use that line, with an appropriate color code, but nothing. Which code sequence will I use, AND WHERE will I insert it? Thanks so much in advance. Also, count on a donation coming soon.