@LD330 said
"I am practicing hatha yoga (Liber E style asana and working through the beginner program in "Light on Pranayama" by BKS Iyengar) and have practiced concentration meditation in the past. My practice right now is not that strenuous. I do 25 min of asana and the prayanama practice takes around 20 minutes (both 6 times a week). I've been fascinated with the idea of dhyana ever since I read Book 4."
How long have you been doing your asana practice at this length? I do Jnana Yoga and so my experience may differ from yours (for other reasons than just the different Yoga style!) You want to "conquer" your asana; whenever proprioceptive sensation "melts" away is fine. Then begin practicing dharana. Boredom and mental fatigue (NEVER overdo it!!!!) were my first major hurdles to overcome. The former and the latter are overcome by the same process: regularity and perseverance. The former has the added obstacle of nagging thoughts: "you did good enough, take a rest and try again later" is one common complaint, "another focus of meditation will suit you better" is another. Ignore them. Stick to your regimen and record it in your journal. Eventually you want to get to the stage, or at least I did, where you are doing sitting meditation in your asana (practicing dharana) for one hour at a time, 2 to 3 times a day. And the rest of the day you are keeping your reactions to the things going on around you to a minimum. This is important because you are trying to still the mind, and activities "in the world" seek to stir it up. (My "Psalms of an Aeon" #1, in the Mysticism section of this forum, is about practicing temperance and equanimity of mind while engaged with the social sphere of work and family.) Taking up a mantra and trying to keep it going when you are catering to your familial and/or financial duties is a good way, in my experience at least, of keeping the mind focused on the Great Work. My favorite mantra: "The joy of dissolution all". (Runner up: "No one is doing this. No one is thinking this.") The Hindus call the desired practice Abhyasa, which is basically "sustained mindfulness of God" or, in our language, of the Great Work.
Keep at it. Don't give up. Be mindful of your practice. These are the keys to success. Don't lust for result.
That's my quick (and probably shoddy) advice that I can lend right now after a long day of work. Let us know if you need any help/support/etc. and this forum and its great cast of characters will do what we can. Shanti.