My technique requires puppetry of four, and keening of one. Usury of four also comes in very handy as I shall explain. Once you have been attuned to your favorite shapeshifter, skinride it. If you want it to switch forms, the shapeshifter has to be in control of it's body. Use keening of one to anger it! Roll keening and charisma difficulty of the current moon. As always, you need four successes to make it frenzy so I suggest spending a willpower point. Once you've pissed it off enough to make it frenzy it's gonna switch forms. Now, use puppetry of four to rein in the mind. If you want to change it back, let it regain control of its body and use keening of two on it. It soothes the savage beast.
Okay so you've got a crinos shapeshifter. How can I keep it with puppetry of four for longer than one scene? Well I'm glad you asked. I don't suggest using puppetry of five because if you do, it's soul is gone and you can no longer make it frenzy. If you want to hang on to it what you need to do is to take advantage of it's regenerative abilities. If you have usury of four, that can turn the shapeshifter into an infinite source of pathos while its in crinos! Be careful not to kill it though!
What about gifts? Well wraiths have no gnosis either, but if the shapeshifter has any gifts that don't require gnosis, have at it!
Have Fun!