I want you to do something for me.

[Zach]

Would anyone mind telling me how to say "I want you to do something for me" in Spanish?

Would it be this?

"Quiero usted hacer algo para mí"

Thanks!

[sosia]

"Quiero que hagas algo por mí" It's a not very formal way (your direct translation) only for friends or your sister
"Me gustaría que hicieras algo por mí". is more polite. For everybody
"Desearía que usted hiciese algo por mí" formal polite way. For strangers or old people.

[Tomisimo]

Zach, if you havn't started learning the subjunctive yet, now is the time ;D hagas, hicieras and hiciese are all subjunctive.

[Eric]

In my opinion subjuntive is difficult, but once you learn it then it's all downhill from there. Que tengas un buen dia!