Photographing children, whether they are toddlers, or babies or in between, has never been easy. Most often as soon as they see you with a camera they become shy and often don't want anything to do with it or you.
You must learn to photograph children on their own terms. It is always easier if they are rested and well feed. A sleepy or hungry child will not make for a good subject.
If you intend on photographing them on an unfamiliar location they can also become quite restless and hard to work with besides showing their emotions clearly on their face.
Try to find a photo location where the kids have been to before and are familiar with it. If this is not possible, then allow them to become familiar with their new surroundings before even considering photographing them.
Don't ask them to pose, instead focus on letting them be themselves. Avoid using flash since they will quickly become aware of it and will more than likely be hesitant to allow photographing them.
Use natural light whenever possible, if the light conditions are not the best where your subjects are, then gently persuade them towards a more suitable light setting.
A good idea is to have some of their favorite playthings at hand and placing them wherever the light is more suitable for photography. If the children are a little bit older, then engaging with conversation or playing word games might get them to stay still for a while. Snap the shots while they concentrate on something else besides yourself, the pictures look more natural this way.
Pay special attention to facial features, focus on their expressions of joy, amazement or curiosity upon discovering something that calls their attention, such as a new bug or a new toy. If the kids have their parents nearby, then capture images of their interaction as these images can be very tender examples of family life and human interaction.
Also good to do is to engage your subjects in the photographic experience by showing them the equipment, explaining its functions, and if using digital, letting then see some of the images, even possibly letting them take a couple of photos of you or their parents.
Remember to use various angles and to try different perspectives as well as to take images at their eye level. Photos taken at eye level seem more real and less intrusive than overhead shots.
As far as babies, the same suggestions apply as for toddlers, letting them rest and be fed will make them more adaptable for photographing. You best samples will probably involve any shots that capture interactions between them and its parents. Very tender images can be captured when a mother holds her newborn, breastfeeds or cuddles.
Props can also be useful if you need to add a little touch to the scene, but choose props that will add to the scene. An example would be a little girl in a flower garden, a beach ball does not add anything to the image, it rather distracts, but a watering can completes the image, better yet, have the child pick up the watering can and water the flowers.
If some of your shots will be close ups involving the face and the eyes, then you may want to add a catch light, which is nothing more than a light unit whose center has been made opaque with only the rims allowing light to escape. This adds "small highlights" on the eyes which in turn make them sparkle and full of life.
Most of these images are normally for family use, but good examples can be used in the greeting card industry and general photo publications and by photographic stock houses.
Not all photographic projects need to be undertaken with the intention of making a profit, but photographing children is easily one of the easiest to do and make a sale.
Children portraits are very appealing to parents and tackling such a project can provide the photographer with new avenues of work as well as providing ample practice with which to hone ones skills.
Parents will likely appreciate their children's portraits if they get away for the more traditional portrait shoots usually carried out in a studio and in very formal settings.
Just keep in mind to exert yourself in an attempt to capture good examples that transmits the character of your subject to the audience. Images that seem natural and not posed are usually very much appreciated by not only an image's audience but by the protagonists as well.
Also ensure that your images are ones that are technically up to par. The most beautiful image is worthless unless everything is sharp, clear and correctly exposed.
If undertaking this project from a business perspective, then take a sampling of prevailing fees for similar work and charge accordingly.
Try to aim for the early morning or late afternoon hours so that the weather is on the cool side. It will make the entire experience more enjoyable for all those involved.