You say that we should meditate for at least 2 to 3 hours per day if we are to evidence rapid and substantial changes in our experience.
Is it best to do this in one sitting, or spread over the day, in say, four or five different sittings?
It is usually better to meditate a number of times during the day and evening rather than for one, two or three hour session.
The reason is that you will find it almost impossible, at this stage, to keep the mind truly still and silent for two to three hours. 10, 20 or 30 minutes at a time is effective for this reason.
Also, it is VERY important that you MAINTAIN awareness of the One Infinite Awareness You are - Consciousness - THROUGHOUT the day and night. It is of little value, and little fruitage, if you have, let's say, one long period of Silence - even if that period is two or three hours - and then promptly begin to be drawn back into the material sense.
It is the CONTINUED awareness of, and resting in, the Invisible Silent Self that "does the work" of revealing All Harmony, Life and Abundance as you, right where you are, now.
See how you get along. Occasionally, if you feel like it, and if you can, keep meditating for as long as you want to stay there, deep within, basking in the blissful Silence.
In the early days, I was advised to meditate for just three to five minutes at a time, but I didn’t feel as if anything had been "achieved", and so my mind still worried incessantly. The worrying, fearful, busy, mind cannot be a transparency through which Spirit pours into tangible evidence. The STILL mind, with its awareness on Spirit - the Consciousness it IS - is the secret.
IT IS IMPORTANT THAT YOU DO FEEL AS IF YOU HAVE GIVEN YOUR MEDITATION ENOUGH TIME - that your period of silence has "flooded" your being. That is how you begin to trust the Miracle Within, the Spirit that You Are. Always wait patiently and quietly, still and attentive, in the Silence AT LEAST UNTIL you feel a sense of Peace permeating you. That is when the "work" of Spirit has been achieved in your consciousness - the Light has dawned - the Substance has become evidenced within.
The best advice I can give you is to go with what FEELS RIGHT, or FEELS GOOD to you. In other words, come up from meditation WHEN YOU feel as if the Peace has been experienced within. You'll feel it. You'll know when that experience happens, even if it is ever so gentle and subtle. (Read in The Miracle Self about the need to FEEL Spirit actually HAPPENING within.)
The feeling, and the amount of time it takes to happen, is different for everyone, and often different from meditation to meditation, but YOU are the one that matters!
Sometimes, you will begin to find that even 30 seconds or a minute or two will permeate your whole being with a sense of Spirit so strong that you just know everything in your body and life has blossomed.
Let the FEELING WITHIN be your guide. Then you cannot go wrong.
Then, as you step back into the sense of the material world with its material-seeming relationships, activities, projects, business, objects, processes, separations and distances - plus its good and discordant appearances - DO NOT ALLOW YOUR ATTENTION TO BECOME ATTACHED TO IT ALL.
This is where thousands "fail". They meditate beautifully, they experience Peace glowing within, they feel flooded with the Infinite Allness, but then, within seconds or minutes of opening their eyes to the material appearing sense-world, they are right back worrying or feeling pressured by its demands, its threats, its urgency, its limits, lacks and discords. I know this well because I used to be very good at it!
The great secret of demonstration is to KEEP mind OFF every material-seeming appearance, and ON and IN the infinite One Spirit that You are... the Awareness, or Consciousness (whichever synonym you prefer) that IS the Allness of the Infinite Self, Itself, BEING You, right here, right now, fully, blissfully, effortlessly, completely... AS your every need fulfilled, revealed to be ALREADY here, for All Good is omnipresent, fully formed eternally. It is what You Are.
A wonderful instruction and meditation on KEEPING awareness permeated with the One Infinite Self all day and night is here:
Being Aware of Awareness Itself Is The Key