preparate/preparaos para la natacion (singular/plural, informal)
natación This is 'swimming' the noun, not 'swimming' the participle. 'Swimming' the participle is nadando. To say, "The swimming team is swimming." in Spanish, you say, "El equipo de natación está nadando."
swimming is nadar and walking in camina
To swim or swimming in spanish nadar.
Swim means nothing in Spanish. In Spanish, the verb "to swim" is "nadar."
Nadar- to swim
swimming
They swim/they are swimming
nadar
The proper translation of get ready is: prepararse
As a question: Is it ready? or Are You Ready? As a statement It/he is ready.
May we go swimming - podemos nadar juntos?
Ready