When doing table top yoga pose, I often like to move towards it gradually, in stages. That's because it involves moving the shoulder blades towards each other and bending the thoracic spine backwards all at the same time.
Once you get the shoulder action and the chest action in this basic yoga pose, then you can add the legs.
To make it easier to feel your shoulders and chest, focus on relaxing them completely and then on lifting and opening. Moving between these two extremes will make it easier to feel your body.
As an added bonus when sinking downwards from table top yoga pose, you can focus on relaxing your shoulders completely so that you may get a stretch at your pectoralis minor muscles, rhomboids and serratus anterior.
For the stretch, focus on relaxing first. With your hands on the floor behind you let your ribcage sink down between your shoulders. You can round your back as you do so.
As you sink down from table top yoga pose, your shoulders will move up towards your ears (though actually it is your ribcage and head sinking down towards your shoulders!) The more you let your ribcage sink down the more you'll stretch your pectoralis minor, rhomboids and serratus anterior. As you sink down notice how your collar bones and shoulder blades move upward relative to your chest.
Following the instructions below, you can lift up into table top pose (or its variations) and then return to this stretching position as you relax downwards.
The first part of table top involves practicing moving your shoulder blades together while your hands are on the floor behind you. (Moving the shoulder blades together is also known as "Retraction.")
As you move your shoulder blades towards each other you'll notice that this causes your chest to move forwards because your hands are on the floor. This action uses the romboids to open the front of your shoulders.
Opening the chest is not the same as opening the front of your shoulders although the two actions can go together when doing table top yoga pose. As mentioned above, to open the front of your shoulders, move your shoulders back so that your shoulder blades or scapulae move towards each other. (You may also notice the ends of your collar bones moving back.)
To open your chest bend your ribcage and thoracics spine backwards. To do this you can use your spinal erectors, the muscles that run up the back of either side of your spine.
To make doing these two movements easier, use the following steps:
As mentioned above, you can focus on the relaxation portion of this exercise as much as the lifting up portion. When relaxing, focus on letting your ribcage sink down between your shoulders. Focus on feeling your shoulders as you do this. You may get a feeling like your ribcage is handling from your shoulders.
When lifting up into table top pose, I like to bend the spine backwards first because this action goes better with an inhale, but also so that the ribcage then provides a stable foundation for the shoulder action. You can try moving your shoulder blades together first and then bending your spine backwards to see how it feels. Eventually you can work at doing both actions together.
Once you are comfortable with the shoulder and spine actions you can work at keeping your chest and shoulders open while using your legs to lift your pelvis. I don't have any pictures, but I often do this first with the legs crossed. Use your leg muscles to press your feet and/or into the floor. Your pelvis will press up as a result.
So that you work your legs evenly, in a balanced fashion, try alternating the cross of your legs. You can do the following sequence of movements:
Once you are comfortable with this exercise (you can use it as a warm up for your legs, spine, shoulders and arms) you can put your feet flat on the floor.
To lift your pelvis higher, focus on pressing your inner thighs down. (This activates adductor magnus, the "fourth hamstring".) Use this action to help "drill" your feet into the floor. (If you like, focus on pressing down through your heels. But keep the fronts of your shins pointing straight ahead.)
Finally you can add your legs for the "proper" table top yoga pose. As before, move your shoulder blades together and open your chest by bending your spine backwards. Feel your feet and pelvis. Focus on using your thigh muscles to press your pelvis up and your feet down. You may get a feeling like you are trying to drill your shins into the floor.
When exhaling and relaxing you can either go all the way down or half way down. Then go back up again on an inhale.
If you only drop half way down try to keep your shoulders active and your spine bent backwards.
For an extra lift for your chest imagine using the top or front of your shoulders (and chest) to pull the front of your ribcage up and back (away from your knees.)
In the picture I'm keeping my head level with my ribcage. You can try dropping your head back. I prefer keeping my head level because then I can use the muscles at the front of my neck to help open my chest further.