I've created a small online store selling Abercrombie & Fitch hoodies. The site is built using Magento. But I've very low traffic though my price was very competitive. Should I use SEO or PPC advertise for it? Thanks in advance.
Yes you can. You may do whatever you can, maximize the resources besides these are for free doing it yourself.
If you want instant traffic & visitors then try PPC...SEO is also very useful for getting long term ranking for your keywords
The PPC would be excellent for short terms but SEO should not be neglected. Getting your site on the top of search engines can be sometimes better than a PPC campaign. You should take extra care to set up your PPC campaign as not every click will result in an order.