If you don't have one of these..... 

to help you do this........................

You really need to get one.  I'm not sure you can tell that there is a ridge on the back that grips the seam as you cut off the excess. 
I love this little ruler.  I use it to trim off the triangles and it's especially useful when I'm paper-piecing and need to trim the seams.  There is also a 1/8 inch ruler to use for mini-trimming.  Of course being the gadget person that I am I have them both. 
I use this one all the time....... but....... I don't think I've ever used the other one ...... yet.  hahaha

I worked on sewing more strips today and I put together three more blocks.  Don was home all day and I had to stay under cover.  He even kept coming in the room every so often to visit with me. 
What's up with that?    

I am totally convinced that pressing some seams open is the way to go for me. 

I've found I can be much more precise in matching angled seams if I press them open. (shhhhh don't tell the quilt police)  lol
And I like the added benefit that there isn't the extra layer of fabric that is there when seams are pressed to the side.   I can't feel that bump.
It takes a bit more time that's for sure....but I'm liking it.
And I 'm especially liking the accuracy that results for me.