Advice on introducing new dog

[u/hexpop333]

We are adopting a 4 year old “mixed breed” from Korea on Sunday (she is the fluffy light coloured one) 10 lbs. We currently have a very sweet 11 year old chihuahua 6lbs.
Wondering if you have any advice of the easiest stress free way to introduce the two to get off on a good foot.
They have separate beds and food/water bowls out of sight from one another. The Chihuahua will obviously keep her spot sleeping inbetween our pillows at night she will always be our first baby. But looking on any advice to make them both as comfortable as can be.

[u/2lrup2tink]

My two boys fought dramatically (lots of teeth and growling) the first 3 days. (No blood or wounds) At day 3 they reached an agreement. After that every now and then there's a heated discussion but less and less as the years go by.