first of all u should apply visa online.then u should have an invitation letter from the person who is inviting you to Ireland,their 6 months bank statement,utility bill,and their passport copy.
Then from your side u should collect an eployment letter for embassy,6months bank statement,details of the property u own in Qatar,pasport size photo.send it to embassy of ireland Abu Dhabi along with original pasport only through Aramex courier service.for more details feel free to watsup me on 33711439