Formal:
* J'ai nettoyé la chambre. (This is the most common and literal translation.)
Informal:
* J'ai rangé la chambre. (This means you tidied up the room, putting things away.)
* J'ai fait le ménage dans la chambre. (This means you cleaned the whole room, including sweeping, dusting, etc.)
Using the passé composé (perfect tense):
* J'ai nettoyé la chambre. (This is the most common and literal translation.)
* J'ai rangé la chambre. (This means you tidied up the room, putting things away.)
* J'ai fait le ménage dans la chambre. (This means you cleaned the whole room, including sweeping, dusting, etc.)
Using the imparfait (imperfect tense):
* Je nettoyais la chambre. (This means you were in the process of cleaning the room.)
* Je rangeais la chambre. (This means you were in the process of tidying up the room.)
* Je faisais le ménage dans la chambre. (This means you were in the process of cleaning the whole room.)
Using the present tense:
* Je nettoie la chambre. (This means you are currently cleaning the room.)
* Je range la chambre. (This means you are currently tidying up the room.)
* Je fais le ménage dans la chambre. (This means you are currently cleaning the whole room.)
The best way to say it depends on the context and the desired level of formality.