Tables are pretty important, in fact nothing else even really matters if you can't reach and use the tables easily. Luckily, you can't really screw them up too much. Find a naming convention that you like and stick to it, I prefer Ricks. (CustomerT, CustomerID, etc) some people like tblCustomer or just Customers, as long as you stick to a theme through the whole database you'll be OK. About the only thing you need to worry about with making tables is making sure you have your relationships setup right. Here's a few videos that might help

Relationships
Too Many Tables
Normalizing Data

You'll never get your tables 100% correct the first time. I'm still modifying tables in databases that are 20 years old. I just spend most of my time teaching forms because that's where you're going to spend 90% of your time developing. Table stuff is relatively easy.