SEO optimization is important to rank high on Google and draw attention of potential customers. However, the content you fill your website with has to maintain this attention and turn website visitors into customers of products/services you sell as an affiliate. Popular ways of promoting affiliate offers include writing honest product reviews, using in-text content links, email marketing activities and offering unique discounts and special offers.
The basic strategy is this: Post interesting content consistently with relevant hashtags. Use a service like Hashtagify for hashtag ideas. Follow users in your niche and engage with their posts. I also know a couple of people who grew their Instagram accounts quickly solely depending on shoutouts from influencers. You can use a service like ShoutCart for that or contact influencers directly (most of them list their email addresses in their bios).
A decent computer. Making videos can consume your computer's processing power and RAM. If you're making long videos, doing lots of editing and recording, your computer will need a good CPU and a decent amount of ram. A good idea is to test your current computer out and see how you get on. If you find video capturing to be sluggish or video editing software keeps crashing, it's usually a sign that you need a better computer. Upgrading RAM is very easy and cheap to do; but a good high-end CPU can cost north of $200 these days.