Kaṭakā Vardhanianaka. This is the combination of two Kaṭakāmukha hands i.e. one is placed on another at the wrist.
This is employed to represent movements concerning wooing a lady or in bowing down to a venerable person.
Kaṭakāvardhamānaka—When one Kaṭakā (mukha) hand is placed on [the wrist of] another Kaṭakā [mukha] hand, the Kaṭakāvardhamānaka hand will be produced.
It is to be used in movements connected with love-making and in bowing [to a person].
When one Khaṭaka (half-closed) hand is placed upon another, the combination of hands is Khaṭakavardhamanaka.
It should be done for love-making and bowing.
Kaṭaka-vardhana (link of increase): Kaṭaka-mukha hands with crossed wrists.
coronation, ritual (puja), marriage blessing.
According to another book: Kaṭaka hands are crossed. The patron deity is Yaksa-raja.
deliberation (vicara), the erotic flavour (Srngara rasa), pacification, (the dances known as) Jakkini natana and Danda lasya, certainty.
Kaṭakavardhana. When a Svastika is made by placing two Kaṭakāmukha hands at their wrist, it is called Kaṭakavardhana.
When two Katakamukha hastas are crossed at the wrists, it becomes Kaṭakavardhana hasta,
Kaṭakavardhana hasta is used to denote the following: coronation, ritual or worship, blessing at the time of marriage, and marriage etc.
When two Katakamukha hastas are crossed (at the wrists), it becomes Kaṭakavardhana hasta.
This hasta is used to denote the following: deliberation, Srngara rasa, pacifying the angry, certainty or taking a decision, Jakkini natana and Danda lasya.
Khaṭakāvardhamānakah The hands which are in Khatakamukha Hasta are kept close and face each other.
This Hasta is used to depict decorating the stage, making garlands and speaking the truth,
Kaṭaka vardhamāna: when the kaṭaka formation is put upon the kaṭakahasta it is kaṭaka vardhamāna.
(Edit note - this real is a self-referential translation. The image provided is a best guess)
It is applied to show the holding of weapons, spear, etc. and the playing of kahala (a large drum).
If the kaṭakāmukha hastas are placed one over the other, crossed at the wrists, it is kaṭakāvardhamāna. A few scholars opined that the hands must be held facing each other.
This is used in acceptance of areca nut and leaf, and other erotic acts and in bowing at the piqued heroine’s feet.
When one Khatakamukha hasta is combined with the other hand in Khatakamukha, it is called Khatakavardhamana hasta.
A conch, the female organ of regeneration, a sword, the spadix of a plantain tree, salutation, a gold pitcher, a silver pitcher, a bell metal pitcher,
pitchers carried by milkman, other vessels, a kunda flower, ordinary lilies,
the holding up of an umbrella, the heart, union—in these is Khatakavardhamana applied.
when the hasta is placed on the mouth;
Khatakavardhamana means a conch
when the hasta is held below the navel;
it denotes the female organ of reproduction
when the hasta is obliquely let fall;
it indicates a sword
when the hasta is held on one side
it speaks of the spadix of a plantain tree
When Khatakavardhamana is held on the forehead,
it is an indication of namaskara.
When the hasta is placed on the left part of the buttocks,
it denotes the subjects from a gold pitcher to other vessels’.
When Khatakavardhamana is held at the front,
it stands for lilies, a kunda flower, and lilies in general.
When the hasta is held above the head,
it means the holding of an umbrella, etc.
If Khatakavardhamana is brought from the top to the heart,
it means a heart.
If the hasta is held across at the front and its tips touch the heart,
it indicates union.
Two khaṭaka(mukhas) placed at the wrists (crossed) [form] khaṭaka vardhamana.
When khaṭakāmukha hands are crossed in svastika at their wrists or face each other, the [gesture] is known as khaṭakāvardhamānaka.
It is used in receiving betel leaves, in amorous persons making gestures of first love and in stringing flowers etc. Some use it to tell a truth.