K, welcome to Money.SE.
You knew enough to add good tags to the question. Now, you should search on the dozens of questions with those tags to understand (in less than an hour) far more than that banker knows about credit and credit scores.
My advice is first, never miss a payment. Ever. The advice your father passed on to you is nonsense, plain and simple. I'm just a few chapters shy of being able to write a book about the incorrect adviceincorrect advice I'd heard bank people give their customers. The second bit of advice is that you don't need to pay interest to have credit cards show good payment history. i.e. if you choose to use credit cards, use them for the convenience, cash/rebates, tracking, and guarantees they can offer. Pay in full each bill.
Last - use a free service, first, AnnualCreditReport.com to get a copy of your credit report, and then a service like Credit Karma for a simulated FICO score and advice on how to improve it. As member @Agop has commented, Discover (not just for cardholders) offers a look at your actual score, as do a number of other credit cards for members.
(By the way, I wouldn't be inclined to discuss this with dad. Most people take offense that you'd believe strangers more than them. Most of the answers here are well documented with links to IRS, etc, and if not, quickly peer-reviewed. When I make a mistake, a top-rated member will correct me within a day, if not just minutes)