I have discussed this issue in detail in my following article which may be seen: Burden of proof of service of notice in cheque dishonour case, what if accused avoiding service?
As regards your second question, let me state that, yes, you or someone else on your behalf can personally go and serve the notice on the person who issued the cheque which has bounced, in addition to sending it by registered post.
Please keep in mind that Section 138 of the Negotiable Instruments Act merely says that a notice has to be given to the drawer of the cheque; it does not lay down how the notice has to be given; in particular, it does not prohibit personally handing over the notice to the drawer of the cheque.
Of course, if you personally serve the notice on the drawer of the cheque, you should take his signature of having received it as acknowledgement (if possible, with his stamp) and/or other evidence should be collected to show proof of service on the drawer of the cheque.
Dr. Ashok Dhamija is a New Delhi based Supreme Court Advocate and author of law books. Read more about him by clicking here. List of his Forum Replies. List of his other articles. List of his Quora Answers. List of his YouTube Videos.