Yeah, I meant the Therum mining laser experience glitch, should have explained myself better.
It's very easy to do, but if you're not patient, you won't like it. Using the glitch is much faster and playing through the game twice though, it normally takes me about two hours of using it to reach level 55 and then I play the game properly from there. If I played on PC I would use the console but sadly, I'm stuck on Xbox.
What I do is rescue Eden Prime, go to the Citadel and ignore all the side quests except for Emily Wong's and Conrad Verners, go to Therum, use glitch to level 55, rescue Liara, come back to Citadel and do the rest of the Citadel side quests, then I leave the Citadel and start playing the game proper.
If you do Liara's mission early on in your play through there's no point in using the laser glitch to reach level 60, mainly because the number of experience points that you get from level 55 onwards is ridiculous. I normally reach level 60 during Virmire.