Here is a great core-strength handstand drill to do at the wall.
1. Place a foam block or a rolled up towel between your legs and give it a good squeeze.
2. Place your hands facing the wall shoulders distance apart.
3. Spread your shoulder blades apart, draw them down your back and firm your outer arms in. Don’t let your elbows bend.
4. Fix your gaze between your index fingers. Do not look back at your feet.
5. To get up kick your heels towards your bottom, shift your weight towards the fingertips and move your butt towards the wall.
6. Now lift and lower your legs keeping your inner thighs squeezing around the block and your hips anchored back towards the wall to create a pivot point. Those of you with tight hamstring will have to keep your knees slightly bent.
7. Keep smiling. :)