When one is doing it, is it better to sit on the floor and stare at a point on the wall with the eyes open?
Or can you sit in a comfortable chair & close your eyes?
Will one method create more of a lasting change than another?
Whatever works best for you. Try different variations and see which helps you reach where you are going, the best way for you.
You will go through periods of difficulties and internal struggle, you will also go through periods of outstanding clarity and peace.
I would say: this step is akin to training wheels on a bike, when learning to ride. gradually you find you need it less and less and can travel further and futher each time without them. Sometimes people try to take them off too soon and end up putting them back on for a while.
Though later it is fun to revisit them from time to time, to remind you what the pure experience feels like and to see if you have strayed off the path.
Then as Flow83 says:
One of the keys to lasting change is integrating that state you get into - maintaining that state of awareness. When you are in that zone, instead of just "ending" the session, do gradual steps.. eyes half open, basic movements, basic speaking etc while noticing the internal shift back into "regular" states. You will learn to integrate the two rather than separating everything into now i'm doing internal work, and now i'm in life.
Gradually you will learn to be able to access it all the time, further on - in a heartbeat.
It becomes less something you do, more a part of who you are.
Quite often I do so when sitting on a train, full of people, or some other busy place. Or whilst waiting for an appointment or standing in a queue, without thought, it happens.
First you do the basic training, then you see where it takes you from there. The basic training gets you used to the state, how it is, how it feels, how your mind works. Then it becomes automatic after a while.