You start with a penance for 41 days, where you keep your physical and mental body clean. Clear your mind of impure thoughts, and develop the ability to remain calm when faced with extreme emotional influence. Specifically people are advised to control anger and not use any foul language. To signify the beginning of this penance, you put a "mala", a chain made of sandalwood or other wood denoting to others that you have begun the journey to reach Ayyappan. Immediately after this ritual, people will also start refering to you as "Ayyappan".
After you kept your promise to yourself during these 41 days, you will need to carry what is called an "Irumudi"; literally meaning "two bags". The bag, actually one bag, that has two compartments, where one is reserved for all the items that are going to be your offering to Ayyappan. The other compartment is for personal items, that you typically require for your journey, ie eatables etc. In earlier days, food was not available near the Sannidhanam, and you had to come back to Pamba. But these days, more offerings are carried in these portions, because of access to food during the journey back and forth.
With a good irumudi, you are now ready to proceed on your journey. There are many ways to reach the Sannidhanam. I will focus on the shortest, which is not necessarily an easy one. The one that i have used. The closest town to the Pamba river entry point to the Sabarimala is Nilakkal. During peak seasons, the government will require all private transportation to stop at this town and then use the KSRTC (government) bus service to reach the Pamba. From Pamba, you take a quick bath in the river. There are times when the water is running very low, and also the bathing ghat can be crowded, and also dirty. For many reasons, the bathing has become a courtesy or a forgone ritual to many. You pay your respects to Pamba Ganapathy and begin your hike.
A good hike, with the irumudi on your head, which is not very heavy, but soon becoming very burdensome, as you climb the steep hill. Since the path is not paved (atleast till the last time i went), there are other obstacles that you encounter. Sharp stones, slippery slopes especially during rain, but one thing is for sure, there are no wild animals. You reach the main temple zone, and you have one final ascent, the 18 steps to the Sannidhanam. These are at a very high gradient, and you are nearly falling on the person below as you climb up. Once you cross the 18th step, you are in front of the entrance to the Sannidhanam. That's when the truth will hit you. It should it.
Written across the entrance of the Sannidhanam, in huge letters in Malayalam and Devanagari script, is what you were looking for; "തത്ത്വമസി" & "तत्त्वमसि" - "Tat Tvam Asi". Meaning "Thou are that".
You are the one that you seek. After all this journey, this simple truth is revealed to you. That the "one" that you seek is in "you". That God is in you. That God is you. That God and you are the same.
Did you have to come this far? Did you have to endure this journey? Maybe you did, maybe you didnt. The answer again only is known to you. But the hints were always there. The moment you decided you were going to Sabarimala, and you wore the "mala", you were called Ayyappan, by one and all around you. You had already recieved this information, but it takes time to realize the meaning.
For this reason, Sabarimala is open to all. People of all faith are welcome. People adorn in black or blue, colors that are very different from the saffron that is associated with the Hindus. The significance is very important. Recent attempts to change this notwithstanding, the beauty of Sabarimala Ayyappan was that he welcomed all, with a special love for first timers, referred to as Kanni Ayyappan.
Pray to him, pray to yourself. Seek within yourself. You will find it - Tat Tvam Asi!