Colombia often gets a bad wrap for its fairly insane last few decades, and thanks to the success of some American sitcoms, there seems to be a renewal of that as of late.
You can get by here with much of the same tactics you use at home. Bogota is actually one big ass city. Bogota is fairly safe, and much more than it used to be. This is a bustling metropolis with plenty of busy workers, students, and business types milling about each and every day, not unlike western cities. Bogota is very hip in some parts, and full of some very hot girls who would certainly like to spend some time with a gringo.
You still might get ignored in the clubs from time to time, and the need to find your way into social circles still exists, just not as much. Lots of girls here do now English, but not as many as there should be.
Consider doing some intensive study of basic phrases and terms a few weeks before you come. A little goes a long way.
As far as safety, is concerned, use your head. Things get a little different after dark, and even when in nice parts of the city, the same dangers exist that you would encounter in western cities.
