The standards and customs are standardized by Kaplingattu Namboootiri. As I mentioned earlier, it is basically adopted from Krishnanattam and Koodiyattam.
Requirements on stage
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The three main requirements are:
1. Lamp
2. Curtain
3. Stool
In earlier days, when there is no electric lights used, the Kathakali was performed in the light of a big lamp (about 1 meter height). That lamp provided enough light for the performance. So now also as part of tradition, Kathakali performances are done with that big lamp lighted and kept in front of the stage. That lamp usually will be lit by the fire taken either from inside the Temple or from the lamp which is kept in the dressing room (called as Aniyara).
Curtain (called as Tirasseela) is used just like that used for any other drama performances mainly between different scenes. This is usually a multi-colored cloth piece bigger enough to cover the entire stage. Two people will hold it on both sides whenever required.
Stools are required for the actors to sit. It is also used by some actors to stand on it, especially when they want to simulate the chariot ride.
Some other things which are required for Kathakali at the stage are Shangu, Alavattam etc required mainly for Thiranottam (we will discuss this later).
Rituals
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As we discusses briefly before, Kathakali starts with the "Kelikottu" in the early evening (6.00 PM - 7.00 PM usually). This is to inform the local people that there is Kathakali in that evening.
It is a percussion concert.
There are a few items which will be done before the start of the designated play. The first one is the Arangukeli. It is to give salute to Lord Ganesha (He is the Lord who removes all obstacles). This is done by Maddalam and Cymbals. It follows Vandana Sloka (Again praises for God and Saints). This follows Todayam. One or more artists in the training dress will play some steps inside the curtain. Most of the lyrics are from Hindu mythology. Nowadays Thodayam is not usually performed in stage.
Purappadu starts after this. Usually Purappadu is suppose to give a clue about which story is being performed on that day. Usually the Hero and spouse will come and play the Purappadu. So the lyrics will be taken from some part of the first story. Nowadays, Purappadu is being performed mostly by Krishna and sometimes accompanied by Rukmini/Balarama/Subhadra. Basically the lyrics are taken from the story "Rajasuyam". It is assumed that God is satisfied with the Todayam which was performed just before that and they are coming to bless the audience. Some times the Purappadu is performed as Sree Rama and Lakshmana and some times Pandavas and Panchali and even some times Nala and Damayanthi.
After Purappadu is the Manjutara and Melappadam. If Manjutara is to show the ability of Musicians, then Melappadam is the performance to show the expertness of percussionists. The lyrics are mostly taken from Jayadeva's Geetha Govindam.
After this, the play starts. Generally for some characters, there is a ritual called as Thiranottam. This is basically looking by lowering the curtain half down. Regal characters (eg: Ravana, Duryodhana) will do this Thiranottam mainly by their eyes. the strong (eg: Hanuman, Veerabhadran) and bad (eg: Dussasana, Bali) characters also have Thiranottam which will involve more body movements.
That's all for now..................................