Tips for how to do two jobs (see description)?

So, I currently work a full time job with great benefits. I wouldn't say its something I like to do, I have learned to appreciate it however. Recently, I was offered a 4 month contract overseas for a dream job. Ideally I would do that and come back to my full time job. Would this even be possible? Any tips on how to get leave?

I am based in Canada.

usa jobs
usa jobs resume
usa hotel jobs
usajobs
usa jobs federal government
usa job in ksa
usa jobs
usa jobs login
usa jobs gov
usajobs.gov
www.usajobs.gov
usajobs.com
usajobs
usajobs.gov official