The biggest problem with sites like Zazzle is the temptation to give up. The ste is now so vast that unless you have hundreds (if not thousands) of products in your gallery it can take a while to start to see sales.
As I have said elsewhere, you do need to add products regularly and you need several hundred to really have a profile and a chance of folk coming across your products. I would say that perhaps the most important thing to remember though is quality. Its far better to have fewer products that are high quality than lots that are low quality.
Persistance is important too…. keep adding good quality products and eventually you will start to see sales. Yes, you may see sales even with low quantities of products (my daughter has a few sales even though she has a low number of products – they just happen to be really cute!). The best way to see sales grow though is keep adding quality products at a regular rate and they will come.
Visits to my gallery are now over 77,000 and I have had over 750 sales (that’s a conversion rate of @ 1%, about average I would guess based on ecommerce sites elsewhere). I currently have just over 2000 products and try to add news on a regular basis though it does go in phases according to how creative I am feeling at the time!
Here is my latest sale:



