The one thing you can do to improve your photography, today and every day, is practice. I know, it would be much easier if there was just a magic button, or some great photoshop trick that would instantly improve our images - and I also know that because this post contains neither of those things you may be tempted to skip it! But I promise you, taking out your camera and shooting will help you improve much quicker than anything I could possibly teach you! Why not consider doing some of the following:
Photograph Daily, or at least weekly
Aim to pick up your camera every single day, even if it is just for two minutes. You will be exercising your mind into thinking about light, where the shadows fall, subject forms, depth, perspective and so on. They don’t have to be your best shots, or even ones that you go on to edit and use, but each time you pick up your camera you will learn something, even if it is just a little bit of muscle memory as to where all your camera controls are.
Photograph even when you are not in the mood
Yes, there are days when I don’t feel like picking up my camera but actually, if you can set yourself into a routine of shooting even when you are not feeling like it, you will learn by pushing through a slump and photographing at any time. That said, there are times when I feel that putting the camera down for a day or so is more beneficial, but you don't want to leave it so long that you get out of the habit!
Bring your camera with you everywhere
I take a lot pictures playing in the park or just in the back garden but I need to go even further with this one, and take my camera grocery shopping or to Starbucks! Take your camera with you everywhere, and try to squeeze a few shots in in different locations. (We can get lazy about just photographing in the home - I am hugely guilty of this) If you would prefer not to lug your big DSLR around, you could use a point and shoot, or even your iPhone, as long as you are thinking about light, location, composition etc it doesn’t matter - I find my iPhone much preferable for this.
Don’t rush it
Sometimes we are so keen not to miss a moment that we rush through it. I know that shooting kids gives you a nano-second to react, so why not practice on something that you can really take your time over? You could photograph an inanimate object, or your kids watching TV (same thing) or, gulp, self portraits. (remember you never need to show them to anybody!) Do whatever gives you a little bit more time to think through what you are photographing, and work through some different ideas or perspectives. I find macro invaluable for this.
Consider starting a blog / website
This blog is a big motivation for me to pick up my camera even when I don’t feel like it. (If I don’t shoot, I have nothing to post!) It’s meant I’ve had no choice sometimes but to take photographs, and I share these with you even though they are definitely not my “best” or something that I would put into my portfolio. I know not everyone will be interested in starting a blog so perhaps consider starting a free website, or even just a Flickr account - just to have somewhere to show and present your images. Then make it a goal to share a new image weekly. You will probably find the need to fill your online gallery quite motivating!
Consider a 365 / Project 52 / Photo a Day for a Month
I'm in the middle of a Project 365 for this year, and I have done a Project 52 in the past - we have one here on the blog which gives you ideas of what to photograph that week. You can hop into this or any Project 52 (or 365 for that matter) at any time during the year - or why not take a photo a day for next month?
Photograph Someone Else!
I've spoken before about practising on others, as if you are only photographing your own children, day in, day out, then it can get a bit monotonous after a while! It can be fun to see someone new in your viewfinder - not to mention a welcome break for your own children! Even if you have no intention of ever turning "professional" and only ever want to take pictures of your own children, you might find this helpful practice.
Photography is like any other skill - the more hours you put in behind the camera, the more natural and intuitive it becomes!