When you do start marketing, there are some different opportunities for you. Remember though that you don't want to be pushy or sales-spammy on many of these.
✪ Submit a free and paid resource to the TPT newsletter weekly. The free item must be 10 pages or less. That includes the resource, cover, credits, etc. Everything is included in this count. Currently there is no fee for submitting a paid resource to the newsletter if it is chosen.
✪ Promoted Resources on TPT. You can check out the blog post TPT Promotion Spots for more information.
✪ Pinterest. Remember this isn't about just posting product cover pins. Create pins of your resource in action or staged. Also, try to pin with the 80/20 rule in mind - 80% content (blog posts, articles, funnies, memes, etc that are yours or others) and 20% products (yours). If you want to pin for other people, do it by pinning their blog posts not their products. As I've said before, I don't think pinning parties are good Pinterest etiquette. You can also pay to promote pins on Pinterest. Once your pin is out there, it will keep going! You can also do Promoted Pins and pay to advertise on Pinterest. Looking to learn more about Pinterest? Check out my 30 Days of Pinterest Class.
✪ Instagram. Again no one wants to see product after product. Include pictures of your classroom, family, pets, favorite quotes, etc. If you pay for a FB ad, you have the option to include Instagram as part of the ad.
✪ Blog. On your blog, you want to provide content. In your content, you can do a "soft sell" on a product. The focus should be on helpful tips and information for the classroom. If you have a product that fits the topic, then link to it. Make sure you have great photos to pin it on Pinterest for your content.
One thing to keep in mind that I keep seeing and others keep mentioning as well, do not post your products in FB groups that are not specific for product posting. I belong to quite a few FB groups and most have the rule of NOT posting products. Read the rules and follow them. Think about who your potential buyer is. Unless you are selling clip art or other seller resources, it is most likely NOT a fellow TPT seller. So unless someone is asking for resource suggestions or the board is for posting resources, don't use other people's FB groups for marketing.