What are some skills that are guaranteed to get me a job, and what are skills that employers look for in this trade

The best way to approach this question is to get on the internet and look for articles that simply list skills that are in demand. This might be certain software applications, computer skills, computer languages, engineering specialties. I decided to cover that approach first because it's more valuable, I think, to look over the experts and what job market observers predict as future trends.

In my own case, I would recommend just about any popular computer application or language. Familiarity with popular operating systems such as various distributions of Linux. Database skills such as SQL and the various applications supporting them -- Oracle for instance. It helps to be familiar with popular Microsoft tools such as Word, Excel, etc.. These are tools that are in use in a wide variety of jobs. These are basically utility skills that everyone should have.

I suspect that by "skills", you were referring to specific skills like I've mentioned. But consider that your education in areas like any branch of engineering is surely marketable and valuable. And a lucrative pursuit.

Any mathematics training is valuable, especially higher math.

As far as other, more general skills, be aware that being a good communicator is usually essential for success in better jobs. Writing skills, presentation skills, personal communication all contribute to your ability to work with others, especially teams, to convey your ideas, to explain your points, to help the success of any project. Never neglect these skills. The tendency in todays world is not for projects to become smaller, but bigger and bigger as time goes on. This means that to be successful, you need to contribute to a team. And that means communicating and learning ideas.

If you can master as many of these skills as possible, you will be a sought-after employee. And you'll have lots of fun.

From my experience, it depeonds on what field you are going into. Programming has its own set of skills, usually some sort of C experience, Java, Matlab, etc. For mechanical/aerospace engineering I'd say familiarity in matlab, any CAD software (though solidworks seems to be everywhere), microsoft anything, and some machining knowledge would be super helpful. GD&T (geometric dimensioning and tolerancing) is also super useful knowledge. And I agree that communicating is a huge factor. If you are competent and can get an idea across effectively, you're going to go 10x farther than the person that can't but can do the work perfectly.