My team has programmed a autonomous but it is not very consistent even though we are using sensors. Are there any tips to make it more accurate?

one simple thing you can try is having the robot move slower during autonomous, this will help your movements be more precise and consistent. Personally my autonomous stacks one cone one the stationary and none of my motors move at more than 80 power during the whole thing.

One thing you can do is make a marker or a placeholder that you could use to make sure you are in the same place every match. You could also make it go slower.