The best treatment for malaligned teeth is treatment with braces. The duration of such treatment depends upon the nature and degree of the problem.
If you are concerned about visibility, you can opt for some of the newer techniques where the hardware is less visible, either because it is placed on the inner aspect of the teeth, or because it is white or transparent. However, most of these systems have limitations, and only after an assessment can their suitability to you be assessed. They would also be significantly more expensive than conventional braces.
If you are concerned about duration, there are techniques that allow faster alignment of teeth, within a few weeks. However, this involves alignment of only your front teeth, leaving the other teeth unchanged. Also, the applicability of this system to you also has to be determined by assessment and evaluation of your diagnostic records.
There are also faster, but more intrusive techniques available, such as the use of veneers
or crowns that may be offered as a compromise, but would involve unnecessary removal of otherwise healthy tooth tissue and should, maybe, be used only as a last resort.