Yoga Rahasya Chapter One verse 89

āsaneṣu yathā na eva kramasya niyamaḥ kṛtaḥ |
prathama abhyāsa asinastadvat prāṇāyāmeṣu sarvataḥ ||

There is a particular order of teaching Āsana,
so also an order to follow when teaching Prāṇāyāma.

āsana - postureyathā - according asna - no; not; nor, neithereva - thuskrama - sequenceniyama - observanceskṛta - done; made; accomplished; performedprathamā - primary, initial, firstabhyāsa - practiceprāṇāyāma - extending the breath