Well, you have all the good advice you need.
As an old timer, 50+ years of model building, I never used photo etched parts until about 7 years ago. I swore I never would but times change and in the last 7 years I've gotten a lot better at photo etch, but I'm no expert. My tools of trade? Just like the rest of the guys: two single edged razor blades, smooth jawed tweezers or tiny pliers, and sometimes a chisel blade in a knife handle. I recently bought a photo etch bending machine but I haven't even used it yet. But I will.
As for gluing it down? Small dabs of medium super glue at one end to anchor the piece and then small dabs of white glue or Gator Glue to position the entire run properly. The white glue is so much easier to remove and redo than CA! Once the entire run is down straight and true I use a dental pic or a needle to run medium thick super glue along the bottom edge of the railing to secure it to the deck.
For photo etched overlays, like in gun tubs or other surface mounted stuff I tack it into place with white glue and make sure it's positioned properly and then touch a dental pic or toothpick with thin super glue on it to the edge of the part and the glue gets sucked under the part by capillary action.
The biggest trick to photo etch is to be able to grow a third arm and hand when necessary.
Start small and practice. The beautiful 1/200 Arizona might be a good model to try AFTER you mess up a cheaper kit.
One thing to remember, super glue softens in Acetone but Acetone eats plastic and paint and photo etched parts can usually be reshaped at least once or twice so you can salvage a mess up. Also super glue bonds to plastic but can be chipped off if you shear it sideways, so you can normally clean up a messed up deck with no real damage with the tip of a #11 knife blade.
With practice you will get better. No one ever 'nailed it perfectly' the first time, so don't feel bad if your first effort isn't perfect. A ship WITH railings, even crooked railings, looks better than a ship WITHOUT railings in my opinion.