Yes, essentially the goal is to practice what is called Manonmani Kriya (manas - mind, unmana - turns inward).
What I do is practice the Mahamudra (which combines the three Mudras + Shambhavi mudra) and while holding the breath, begin to mentally rotate the mantra ascending and descending along the spine (central channel). Also, this will not cause any stiffness if done right as one of the pre-requites for this Mudra would be a good amount of Pranayama practices and a good level of mastery over individual bandhas - so that the breath is very fine and subtle. If that is ensured, when holding the breath internally, the effort part is negligible. The main problem would be if we apply too much effort to hold the breath (or for longer than the body permits).
Also, once an energized/attuned mantra is rotated, the capacity to further perfect the mudra seems to greatly increase because now the entire lineage of teachers and the deity personified by the mantra are now present assisting us… 
Of course, this is my way (and just one of the many ways) of doing it. Accomplished folks like Dream get into this twilight state of Void-Light without any acrobatics with just a nod and a wink… (I’ve seen him do that haha)…