Natyashastra
आकृत्या चेष्टया चिह्नैर्जात्या विज्ञाय तत्पुनः । स्वयं वितर्क्य कर्तव्यं हस्ताभिनयनं बुधैः ॥ १६२॥
By observing the form (ākṛti), movement (ceṣṭā), signs (cihna), and type (jāti) of a gesture, the wise (actor) should then, through personal reflection, perform the hand-gestures accordingly.
english translation
AkRtyA ceSTayA cihnairjAtyA vijJAya tatpunaH । svayaM vitarkya kartavyaM hastAbhinayanaM budhaiH ॥ 162॥
hk transliteration by Sanscript