The first thing would be to stop feeling guilty about not being able to spend too much time with your kids. Remember, the quality time spent together is always more important than quantity time.
Never ever resort to using money or gifts, as a compensation for your absence. It will not only spoil the children, but also make them lose the importance of money in life.
Having a helping hand is always a good idea. However, make sure that the domestic help you are hiring is dependable.
Learn the art of time management. They will go a long way in maintaining the balance between office and home.
Find small little ways of connecting with your child, like call him/her daily from office, go for a little walk after dinner to discuss how was his/her day, and so on.
Make it a point that ever week, you dedicate at least one day for your children. For instance, plan your Sunday in such a way that while in the morning you spend time with your family doing household chore, in the evening all of you move out for a family dinner or a family outing.
Do not forget to spend some time on yourself. It is very important for you to be in a good shape, in order to fulfill your responsibilities.