Glad you enjoying GT & making progress with your guitar playing!

"I am not getting the sound I have noticed when Teacher Mike Olekshy teaches About a Girl."

This is difficult to assess without hearing the sound you are getting in order to compare it to the tone on the lessons.

Can you post a link to audio or video with audio of your tone playing the parts to the song?

Most of those songs use a pretty basic clean tone, then engage a basic distortion or overdrive pedal for the overdriven sections.  You might need to make sure your guitar is on the right pickups to match the tone.  Have you tried to set your amp for a basic clean tone, then get the gain from the DS-2?