First of all there are pinned and plain blades - what does your saw take? Then, the type and size of the blades you need will depend on the work. The more intricate the work, the smaller the blade you will need. The bigger the blade the less sharp they will turn. The brand of blade is a personal choice. I prefer Olson, usually #2 skip tooth reverse. I do a lot of very intricate work and quite often go as low as a #2/0 ST reverse. I also like the Flying Dutchman ultra reverse for more open work. As I say, you will have to first find out whether it takes pinned or not first. As you don't have a manual probably the quickest way to find out is to check out what holds the blades in place. If it takes pinned blades there will be a holder where the pins on the blade hook on to. If it takes plain, there will be clamps. Have you tried finding a manual on line?
Hope this helps.
Noel