Here are a few specific questions I have:

1.What are the most important things I need to do to optimize my product listings?

It is necessary to go back a few steps. The most important thing in online retail sales is not product optimization. The three most important things in online sales are product, Product, and PRODUCT. If you are selling a dead product that no one wants, nothinf is going to help sell it.

2.How can I make sure my products stand out among competitors and attract more customers?

Amazon selling is very simple if you don't fall into the traps set to extract as much of your profit as possible, set by vendors selling ad-on products like advertising and inventory management. If you sell products that buyers want and need, and sell them at the lowest cost, they sell themselves with no additional advertising or optimization necessary.

3.What types of marketing strategies have worked well for you in the past?

There is no real answer to that question until you understand #1 & 2 above. There are plenty of vendors you can pay for advice, but if you are selling things you found with "GOOD BUYS", and no one wants them, paying for their service will be of no use.

4.Any other general advice or tips would also be greatly appreciated.

1. It costs no more to fail in online retail sales as it does to succeed in online retail sales. The differences it the amount of knowledge you possess to put forth in your endeavors.

2. Amazon Seller University will tell you everything you need to know about utilizing the site, but how to operate a business for profit is what you bring to the site.

3. Amazon is a for profit company and is very good at taking and keeping as much of you profit as they can, often without you even knowing it's being taken.

4. Only sell product that buyers want and need and offer them at the lowest price. They sell themselves with no promotions or advertising.

5. When sourcing your products to sell, don't even considering buying them if you cannot earn your desired profit (after all fees, shipping, and overhead are included) considering #4 above.

6. Don't fall for the Get-Rich-Using-FBA plan. ALWAYS test sell your product for a month or so yourself. That way you will have a very good idea of the volume of sales per month to expect and can see if the volume is large enough to support the FBA fees Amazon will charge and still make your desired profit.

7. Know your shipping cost to every address in the USA BEFORE you list any product. If you do not, you will lose on every sale.

8. Last, but very important, begin to learn on these threads all the scams Amazon buyers play on sellers. Don't take it personally when it happens. Just about very seller has come across one. Most likely your first one will catch you off guard and making a poor decision in handling the situation will cost you a loss.

9. There are many successful sellers on the Amazon site. Just follow Amazon's policies. Read them and ask questions before you begin to sell, because if you violate one, it just may end you selling ability.

10. I will not say best of luck, because luck has nothing to do with Amazon selling. It is all in knowing how the retail trade works and how you can fit into it.