What kind of marketing and advertising strategies can I use the moment I launch my T-shirt business?

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Instagram. No joke, it is flooded with "instafamous" fashion related accounts that charge anywhere from $5 to $30 per post. Create your own IG, put a tracking link for your site in the profile. Post images of your gear, your brand, your lifestyle etc. Get in touch with said larger accounts for promotions. I have a friend who did the same with bracelets purchased on Alibaba that were generic to those shown on "lifestyle" accounts. A quick buck, sure. But if you want to keep your business growing then make sure you cover your social media based AND utilize a newsletter system to stay in touch with those quick sales.

There are many platforms to choose from: 1. Facebook page (A must for any online business) 2. Pinterest (Probably one of the best way to link it back to your online store) 3. Etsy (it has to be handmade products, 20 cents per post) 4. eBay (This is the best way to kickstart sales) 5. Any free classifieds. Ultimately you should also focus on traditional methods of marketing your products. Good luck!

Others have covered important points aside from that i think instead of going 24–7 through all social media websites ….making viral content might save your ass and best strategy for a startup.which is almost impossible without creativity & unless you bring something new to the table (←- Mandatory).Others are already doing all those social media management BS and as you’re a start-up you won’t get anywhere near ads on television(assuming) Not Cheap Not Wise .Ex- Bewakoof started as a facebook page they still post stuff that are funny and hilarious just to engage people you might do better then them but still you’re just another fish in the river filled with sharks.But thats my opinion Good luck.

Do not pay anything for the advertising initially.If yours fit in a niche, leverage social media by daily creative updates on 2–3 platforms.Get feedback from your initial buyers and improve on the t-shirt as a product and T-Shirt buying experience.Get optimum fit as your niche requires, printing designs, printing type, fabric, after wash effects, packaging, freebies sent along the parcel everything can be optimized over the period of time.