Those actions which are prescribed as duties in the smritis are known as Nitya Karmas .Non adherence to the Nitya Karma results in sin . Daily bath,pooja,ekadashi ,krishnashtami are all nitya karmas.
Karmas ordained for special occasions are Naimiitika karma. Pitra paksha shraddha, Magha snana,Kartika snana,grahana etc are all naimittika karma .These has to be done on a particular occasion at a particular time due to some nimitta . Non performance of these do not attract sin, but if done gives merit.
All karmas done with some desire in the heart ,or to achieve some selfish purpose are known as Kamya karma. These if done improperly results in failure of the desirable , and otherwise assures success. Merits and sins are outcome of the type of desire made. Going on pilgrimage, undertaking parak,kriccha ,chandrayan etc are all kamya vratas.
In all types of karma Vishnu alone should be worshipped. Vishnu alone is capable of giving fruits, others give under his permission and not independently.
Sarva deva Namaskaro Keshavam pratigachchati