Cutting a square hole?
This is a really basic question—I have managed to get to 66 years old and still be a complete handyman novice, I have tried but my best efforts are lamentable. I think it is because I have never had anyone to show me handy things and have never asked anyone so turning over a new leaf I am determined to start making a few things instead of spending a fortune buying them and paying people to do things for me. My first project is to make a simple slide carrier and I have bodged one up in cardboard but it really needs to be in something stronger so it is rigid, metal would be ideal but very stiff board would also do if I can not cut the metal. I do have a thin sheet of aluminium, (from the casing of an old laptop) that I would like to use buy am frightened of messing up & worse injuting myself! I now realize that I have no idea how to cut a square hole in a piece of metal or, for that matter, what tools I need to cut aluminium in the first place!
My overiding consideration is to be safe so I don't want to try, (what to me is a daunting task but probably to you guys the simplest of things) not knowing what I am doing. So can someone please help me out and tell me what tools I need and how to go about cutting a square hole in a piece of metal? Rest assured I will not do it if I do not think I can safely.