How to install a package and resolve dependecies issues

I'm not using any packet manager in Slackware (I don't even know if there's one that can manage dependencies), so I have to install manually the packages I need. Sometimes this isn't so easy, because for running a program you often need other programs or libraries, and they aren't already installed.

So, let's see an example. let's suppose you want to install transmission, a light-weight BitTorrent client.

Step one: find and install a package 

This one is simple: if it's pre-compiled you can find it in your install CD/DVD, in the online Slackware mirrors (my advice is to search the package name in the list of packages, like this one) or on slacky.eu where you should search the package name in the right repository (in my case, 13.37 32bit). There it is: