Master's Degree in Electrical Engineering

Some companies will help you do this. If yours does not, then switch jobs to one that will. Sometimes they will even pay your educational expenses. Ask around.

It seems to me that it is very hard to do both specifically in Saudi Arabia. Because master degree it needs a lot of work and research especially in engineering. My advice to you is you have to look for your aim first. You have to find what do you want to be? and where do you want to work after you graduate? it is very important to think before you make your decision. Because as far as I know that Saudi Arabia has very few companies are looking for masters' degree. Mainly, Saudi Aramco is one of the big companies that might look for some graduate students. Unless if you want to be as instructor in one of the institutions in Saudi Arabia otherwise I think bachelor is more than enough since you have a job.

Good luck