To get the eyes to be crisp and clear, make sure you have a lot natural lighting available. If you are indoor make sure to place your subject by a window. I am very fortunately to have a big window in our master bedroom. I take all of Kaylee's room in there and have her look 45 degree angle toward the window. Using a reflector would also bounce a lot of light into the subject's eyes.
Before Kaylee could sit up I use a white towel as a back drop so it can catch a little light from the window.
The best way to get your child's attention is hold a toy that he/she has not seen yet. It can even be your makeup brush or whatever you find in your purse. (The camera lens always does the trick-if that doesn't work, I seriously hold up our Yorkie while taking her photos..true story) Kids are so curious with new things. The younger ones love anything that make a noise.
Shooting for the shallow depth of field is usually around f/1.4-2.0. It allows me to focus on the sharpness of her eyes while give that nice soft blur around her face and background.
When shooting outdoor, the best way to catchlight is to have your subjects look up. You can achieve just right lighting in their eyes when you are above your subject.
Hope you like these little tips, should I start doing more photography tips? Let me know! Thanks for visiting!