considering subtractive synthesis is pretty much all the same ...you would need to start off by finding a synth plugin/hardware you are comfortable with. then learn as much as you can about that synth.
then, once you have "hit a ceiling" with the synth, (learned everything you can) you can then approach a new synth in the market.
it's best to find a synth that is incredibly robust, expandable and (more importantly) -fairly- user friendly.
i would recommend omnisphere... but there are a lot more forms of synthesis in that plugin. my second recommendation would be native instruments massive. it is extremely easy to use and has a ton of resources available online from the third party developer/user... huge community.
it's a tough nut to crack, once you get started but after a while, the "programming" aspect of it is much more fluent.
groove3, youtube, sonic academy, macprovideo are all great resources for learning new software.
hope this helps some!