problem with orders?? vs required attributes not being enforced

I have attributes set up for colours and sizes on some of my items .I have just noticed a problem when testing the site today. I t is allowing customers to click on a product and tehn add to shopping cart without picking size or colour first.It then shows as out of stock.How can I set it so that customers must choose a size and a colour. My site is https://www.blushfashions.com but if you go straight to this product you will see what I mean http://blushfashions.com/index.php?main_page=product_info&products_id=217
:D

http://www.zen-cart.com/forum/showthread.php?t=4810&highlight=required+attributes

Hi
I have already looked at this thread but it does not give the answer I am looking for.At the very beginning it mentions something about attribute flags but as this is quite an old thread it must relatet o a very old version of zencart.There is no add button, it is now am insert button, and it suggests quote

Then there are the Attrinbute Flags in the colored boxes.

These are used to help distinquish other features of the attribute such as:

Use for display only (attribute cannot be selected and added to cart. Good for things like "Select from Below" to force the customer to make their own choice and not just hit Add to Cart and get a pink snail instead of a blue snail :)

This does not work:cry:

Two ways to do this ...

Set a default on one of the existing colors for the Product ...
Note: problem will be is that really the color the customer wants?

Or ...

Add an additional Color called:
Pick a Color
Sort Order 0
Default YES
Display Only YES

This will set a color that is not allowed to be picked ... and force the customer to select the real color that they want and not your default based on one of the colors in the option values ...