Hi dustysantos!!!
I will try to give you some answer but of course you can find all the information you want just reading the forums or the Support rules.
To be able to sell it is not enough just create your shop. People have to know who you are and what are you designing.
*How long did it take to sell you first item?*
It depends by your design and object, for which kind of customer are and if people like your stuff. It is not easy to know, it could take 2 weeks, one month, really it depends from your visibility.
*Do you have to get an item printed and take a picture of it before it sells?*
YES YES YES YES! As soon as you can try to upload pictures of your real objects! Render gives just an impression and it is better to see the real material with right colors and texture.
*What is the secret to getting a lot of traffic?*
Check here:
https://www.shapeways.com/betashops/how_to_promote_your_shop
There are also a lot of web site that offer advertise but you have to pay.
*Can you give any tips to a new comer like me?*
Keep yourself updated. Be original and try to focus your mind on your design and ideas. Don't design something just for sell but try to pay attentions for all the details.
I hope it could help you, as I told you you can find all your answer here on SHAPEWAYS and the have also a very professional and helpful customer service.
Good luck!
Dario