I had never cut crown moulding before but it actually was not hard at all.
Here is the before shot:
A few tips I have:
Just remember to always cut it upside down. The most decorative part of crown moulding is usually the bottom of it. So when cutting it, make sure its always facing up for your cuts.
To make sure I never forgot this I took a pencil and wrote top and bottom on my crown.
Crown moulding has a flat back portion and then 2 "wings". It is very important that these "wings" are flush against your fence and table of your miter saw while cutting.
You are essentially wrapping crown around a piece of mdf board on 3 sides so when measuring your long span of crown molding account for this in your measurement, I had to add on a total of about 1/2-inch extra to account for this.
It was easiest for me when cutting the small return pieces to just attach to my main piece of crown with Gorilla wood glue and blue painters tape and let it set up over night.
First I measured my door span and cut a piece of mdf to match. I used 5 1/2" wide mdf and using my nail gun installed on top of my door trim.
I had a small gap between the door trim and the mdf so I installed a piece of pine trim to hide this seam. I used wood glue and blue painters tape to hold until dry.
Then measured for my front piece of crown moulding, adding about 1/2-inch to allow me to add small side return pieces. Cut both ends at a 45 degree angle using your miter saw, ensuring the crown moulding is flush against the fence and table of the saw table.
Next I got my measurement for the small side pieces. I held up my crown moulding to the mdf board and measured the distance back to the wall from the top portion of the crown moulding.
These small pieces will have a 45 degree cut and a straight cut. The straight side butts against the wall. I cut the straight part first by laying the crown flat on the table and cutting at 90 degrees.
Then I marked my measurement and cut at a 45 degree angle.
Remember to cut the small pieces upside down just like you did previously.
I'm a visual person so here is what the pieces will look like for the right side before gluing together:
A photo of what the left side will look like before gluing:
Used wood glue and blue painter tape to attach the 2 side pieces and let dry over night.
I painted the crown moulding before nailing it up which saved a lot of hassle.
Used my level and nail gun to attach the crown moulding piece to the top portion of the mdf board.
Filled in nail holes and added one last swipe of white paint.
Off to do the back doors now!
UPDATED TO ADD: