The most common form and word order is "Holnap dolgozom".
The form "dolgozok" is also used by many people, but prescriptive grammars will tell you it is not correct. You may sound uneducated if you use the "-k" ending in the 1st person. Hungarian schoolchildren are discouraged from using it. (The same goes for eszek, iszok, lakok, alszok, instead of eszem, iszom, lakom, alszom.)
This is the problem with verbs that have an "-ik" ending in the 3rd person singular form of the present tense (ő dolgozik).
Good luck, I hope I didn't put you off!