Purush-Charan- means the Charan of the Purush. The difference between Mantra Siddhi and Purushcharan is like the difference between having a family car vs having a sports car. Family car can take you to the desired destination but not as quickly as a sports car. But again, sports car is also very risky. Same goes with Purushcharan. - Ashok Mehta
Purushcharan usually happens by the Mantra according to the words in it.
For example, take the Mantra: ||ॐ हनुमते नमः || it has 6 letters. Mantra Siddhi will require 1.25 lac chants and Purushcharan will require 6 lac chants.
Mantra Siddhi means to unlock the Mantra and its power to use it and Purushcharan means to bring the deity's complete energy in the Mantra after the unlocking
Purushcharan is not an easy task. When you are going to do Purushcharan, it is the same as you are standing on a rock and ferociously challenging all the 3 worlds to try and move you from there.
People abuse their Guru behind his back because whenever you go to him he only gives you one Mantra-the Guru Mantra. And that is where the basic mentality lies which needs to be changed. It is not like I haven't gone through all this. Even I have. But that doesn't mean one must stop learning. Every day I keep on searching for Mantras. I do not search for a Mantra because I want to chant it, I search for Mantras to know their Vidhi because the Vidhi itself tells you a lot about our religion.
Everyone who does is spiritually inclined goes through this phase even I have, but realizing the truth is wisdom.
For people who still do not understand in spite of reading so much that I have mentioned above, go and ask an Aghori about why he left his family. When a person gives up all kinds of desires like TV, women, gambling, liquor and his only source of hope is god, plus the uncontrollable fire within him which wants his Isht Dev's Darshan at any cost; that is when he gets a Mantra and success in unlocking it’s full power.
God is humble but law is law and it cannot be broken due to anyone's comfort zone and ignorance problems.
I have lots of Mantras, thousands of Mantras but there is no point of sharing them because there is always one Shatbuddhi person who wants to do Siddhi over Sadhanas like Astra Sadhana or Baglamukhi Sadhana when in reality he doesn't even have a Guru Mantra firstly. Again, Guru Mantra isn’t an utmost necessity but the dangerous mentality of chanting every and any Mantra can actually create havoc.
What is the meaning of Purushcharan?
Imagine you have got a Mantra. now keep your attention solely on the Mantra and say to yourself "This is my Mantra [say "Om Hanumate Namaha''] and unless and until I don't get Purushcaran over it I will not gain peace and now I am this Mantra Sadhak and i will not move until and unless I get this Siddhi. Now, everyone will come to stop this Sadhana, it may be anyone, my parents, my relative, ghosts, Pisach, Pisachini, all the 7 seas of Santana Dharma will come and even my Isht Dev will come and try to shake or break this Charan of mine but I will not move. Now, No matter how dire the situation gets I will only move when my Purushcharan will get completed"
Use this positive affirmation and begin any Sadhana and you will definitely get success.