Use unshift. It’s like push, except it adds elements to the beginning of the array instead of the end.

• unshift/push – add an element to the beginning/end of an array
• shift/pop – remove and return the first/last element of an array

A simple diagram…

   unshift -> [array] <- push
   shift   <- [array] -> pop
 

and chart:

          add  remove  start  end
   push    X                   X
    pop           X            X
unshift    X             X
  shift           X      X

Check out the MDN Array documentation. Virtually every language that has the ability to push/pop elements from an array will also have the ability to unshift/shift (sometimes called push_front/pop_front) elements, you should never have to implement these yourself.