What are the advantages of an online kitchen design service over simply calling somebody in to do it for you? Cost is one benefit: it is a lot less expensive to do it yourself online than for somebody to come to your home and do what you could do just as easily yourself. Another benefit is that you get exactly what you want, and you can't blame anybody else if it is not to your liking.
Once you have completed all of this, your order is constructed for you, finished to your specifications and delivered. The cabinets can be professionally installed for you or you can do this yourself. Online kitchen design is easy when carried out this way, and knowing how to do this should give you the confidence to design your kitchen online.