Building Upper Body and Core Strength
First thing to work on is building strength in the upper body and core. My favorite prep for headstand and many arm balances for the matter is dolphin.
To practice dolphin, come on to all fours and place your forearms on the mat, interlacing your palms. Tuck your toes under and lift your lower body to come in to forearm dog. On an inhalation, come out towards forearm plank and imagine touching your chin to the floor in front of your fists.