Start with the camera, not the flex
Place your phone upright on a stable surface and frame yourself from the waist up. Leave space above your head and beside both elbows. Face the camera in even light so the outline of the raised arm stays visible. A crowded background or an elbow cut off by the frame can hide the shape even when your hands are positioned correctly.
Build the heart one side at a time
Raise one arm with the elbow bent, as in a relaxed bicep flex. Angle that wrist downward toward the upper arm. Bring the opposite hand across your chest and curve it toward the raised arm to complete the other side of the heart. Check the preview, adjust the gap between your hand and arm, and briefly hold the recognizable outline. Use a comfortable range of movement.
Avoid the common look-alikes
Joining both hands in front of your chest makes a hand heart. Lifting both arms overhead makes a larger overhead heart. The bicep heart pose instead uses one flexed arm as part of the outline. If your recording looks like an ordinary flex, move the opposite hand into view and check that the two sides actually form a heart.
If you would rather start from a still photo
A bicep heart AI video generator offers a different route: choose a portrait and let the service animate the gesture. Our tool creates a 7-second vertical MP4 from one adult photo for $4.99. You do not need to perform the pose in the input, but both arms should be visible. Compare the generated sample first; AI hands and details can vary.