Making a custom UI for a game and importing it to Unity

[Jaeger]

Does anyone know what resolution/dimension I should be working for the UI like : main menu, dialogue box, hud and etc. then how would I import that to Unity?

All tutorials i've found so far just shows me using Unity and making a UI there instead of doing it on a different program.

[Falli]

Depends what you want to do? HD or Pixel Art Game :-) I'm not familar with Unity but I think it should me the same like in GMS2: Save the sprite (.png) in Aseprite, import the sprite in the engine you are using, place the object in the scene/room, add code to it.

Nevertheless I think you should ask in the Unity forum to find help, because the actually problem you have, has nothing to do with Aseprite.