Japanese dictionaries list verbs in this form. If you use this form, you sound more casual. There are a number of ways to make "the MASU-form of verbs" into "the dictionary form." First ...
When you ask somebody to do something in Japanese, you say TE-form verbs and then KUDASAI (Please, or I would ask you to). The TE-form verbs are the conjugated form of verbs that end with TE or DE.