1) Define your USP (Unique Selling Proposition). What sets you apart from all other businesses out there? When you get a good understanding of your USP, you'll know how to position yourself like where you should increase your visibility, who you should target, what should be your packaging, etc.
2) Quality. No matter what you do, if your products are of poor quality, it'll be hard to get repeat purchases.
3) Good customer service. You should be active with a response time of 24-48 hours. Customers are impatient and they hate unresponsiveness. Have a lot of patience and never ever appear rude. Triple check everything before sending. It'll take you a lot of time to build a brand and you can lose it in a snap especially in this generation where "cancel culture" is in. People like jumping on hate trains online.
4) You should always be ready to invest for the betterment of your business. Adapt to the trends and always offer your customers something new so that they'll be on a lookout for your new releases and follow your brand.