Having a good catch is the single biggest thing that helps you get the power on the front of the stroke, if this happens then everything else is easy.
When the blade enters in on its side I call this duck feet paddling, this happens from having your hands down low around stomach to belly button. The way to improve this is by lifting up your hands to having your knuckles at eye level. If you have low and try this you will feel like a monkey paddling with your hands over your head, you need to do it.
Here is a quick video of people with low hands and duck feeding and one with square blade.
The Hope this helps.