I am mindful of my skandas, but that doesn't prevent other's samsaric action, trying to influence me and my practice. What are the different ways of protecting one's practice?
Mindfulness will "protect" your practice.
Mindfulness is a wholesome mental factor (cetasika) and when it is present, one is not reacting to phenomena, i.e. by running away from unpleasant phenomena and running after pleasant phenomena. Instead one is standing still. One is in the present moment, clearly recognizing that it is our own reactions to phenomena that create suffering. An unwholesome thought or anger is still just a thought and a feeling. Its our own aversion towards these objects, that create our suffering.
So by keeping mindfulness at all times, one is protecting ones practice.
I would recommend the video "How Mindfulness Creates Understanding (The Buddhist TV)" by Ven. Yuttadhammo.
There are what are traditionally called the four protective meditations (Caturarakkha)
Buddhanussati - Remembrance of the Buddha (and his qualities)
This would be protecting a sense of purpose in the practice, preserving your faith and confidence in following the path
Metta - Goodwill
This would protect your goodwill and patient forbearance with others who might interfere with your intentions.
Asubha - Meditation on unattractiveness of the body or of physical nourishment
This would protect your mental calm and dispassion in the face of sensual temptations.
Marananussati - Meditation on (the imminence of) death
This would protect your sense of urgency in doing your best while you are able.
On a related note this might be also worth reflecting:
And how does one look after others by looking after oneself? By practicing (mindfulness), by developing (it), by doing (it) a lot. And how does one look after oneself by looking after others? By patience, by non-harming, by loving kindness, by caring (for others). (Thus) looking after oneself, one looks after others; and looking after others, one looks after oneself.
"I am mindful of my skandas, but that doesn't prevent other's samsaric action", such can not be, Mr/Mrs 8CK8. "What are the different ways of protecting one's practice?" Mindfulness, Mr/Mrs 8CK8.
Actually this can be also a hint to improve or rethink your question, ponder a little about and investigate. If Mr/Mrs 8CK8 still thinks, that he is mindful and also understands the clinging aggregates, then he/she should read About Khemaka
(Note: this answer has not been given with the agreement to be means of trade or the purpose of/for trade and/or keep people trapped and bound. How you handle it lies in your sphere, but does not excuse the deed here either.)
This answer is from a Mahasi Vipassana perspective.
The worst influence on us is ourselves and our own wrong view.
If you have no views or opinions then you could feel more secure because you couldn't influence yourself with (wrong) views or let anyone influence you with (wrong) views.
At least while practicing have no views and no opinions. Right or wrong views during practice is wrong view. To have any thoughts on purpose is wrong practice anyway. "Right view is no view" is one way to explain right view.
Let's hope you find a good teacher and they plant the initial seed of right view and good practice within you. Metta
But surely in trying to protect your practice you are still practising a form of grasping at something which has no permanence? Should you just let it go, observe and learn that by letting go you are still practising?