Before anything, invest in an ortho consult!
The best way is to have an orthodontic evaluation. For minor tooth movement, there are multiple options, not necessarily braces. You may be a candidate for a retainer or Invisalign. Other than that some may suggest bonding to close the gap, which may le less costly and faster, however not a great choice. The bonding will most likely fall off, discolor or take away too much of your sound tooth structure.
The most important fact is to do it right so that bigger problems do not arise later on...