One of the cornerstones of SEO is making sure that your metadata is written properly. In regards to YouTube, metadata refers your video title, description, tags, etc. These all play a large part in determining how well your videos rank in the SERPs for particular terms.
Title: Just like in any field of content creation, your title will need to be catered towards both your search engines and your viewership. With this in mind, you'll want to make sure that your title contains your targeted keyword(s) but is also highly relevant to your video. Viewer retention definitely plays a part when it comes to the ranking of your video in the search engines, so having a misleading title will likely prove to be detrimental in the end. This also relates to thumbnails, which we'll touch on later in the post.
Another thing to note is that it's important to have the most pertinent search terms at the beginning of your title, just as you would if you were writing the title of an article. This would include terms such as your targeted keywords, particular niche or general terms that are likely to receive plenty of search traffic, such as "tutorial", "how to", etc. Essentially, your title should act as somewhat of a scale when it comes to search terms, with your more targeted terms going towards the beginning and less competitive terms, such as branding or episode numbers, appearing towards the end.
As you can see from the example above, the start of the title contains "How To", while "Creator's Tip #21″, a more brand/channel related term, has been placed right at the end of the title.
The next part of your metadata that needs to be properly written is the description of your video. Within your description, you're given 5,000 characters to do whatever you wish with. Your description should do a few important things:
Inform, entice and drive.
First of all, you should quickly and accurately describe the premise of the video within the first few sentences of the description, as that is what will appear within both the SERPs and the About section of your video. Accurately describing your video while including relevant keywords within 120-150 characters should be the way to go.
The other 4,800+ characters are also highly important, considering that the entire description is crawled and is therefore associated with your video, so you'll want to make sure that it is all properly written and optimized, and not just neglected.
You could elaborate upon the description that you've written within the first few sentences, provide a proper description of your channel as well as link to anything referenced within the video. For example, if you're doing a tutorial on how to remove links from your website's link profile, you can provide links in the description to the tools that you've used along the way, and possibly any other related content that you've written.
On the topic of linking, it's important that you link to anything else that your viewers can head towards after watching your video, such as a link to subscribe to your channel, links to any relevant videos/playlists, a link to your website, your store, social media handles, etc.
Tags: Finally, another key area of your YouTube video optimization is making sure that your tags are spot on. Tags are the area of your video where you add a myriad of keywords that are related to your video. One thing to remember is that you should avoid being too general when writing your tags. While you don't want to write something that's too long, considering that you have around 120 characters to create tags with, you'll definitely have to put in some proper research and find more specific terms that are going to bring traffic to your video.
On the topic of YouTube keyword research, there are a few ways in which you can find fresh keywords to use, such as the YouTube search bar. You can use this by entering an initial term, then seeing what the most popular related terms are in the list. Another tip is to use common misspellings and rearrangements of other keywords. You can also use YouTube's very own Keyword Suggestion Tool, which could potentially earth some hidden gems.
Another thing to keep in mind is the updating of your tags. After a period of time, you can change the tags of a video to ones which are more befitting of the current trend while still remaining relevant. You can also use the YouTube Analytics service in order to find new tags for your videos, by seeing which terms have been bringing traffic to your content.