Here is the complete procedure to get started.
1. Login to YouTube official website.
2. On the right panel, you'll see your profile icon or image. Click on that to expand.
3. Click or chose the desired account and proceed to creator studio.
4. Under the tab of your dashboard, click on advanced settings.
5. You will be redirected to YouTube profile.
6. You'll see a link called "Verify"
7. Click the verify link.
8. Chose the location and input your mobile no.
9. You will receive an incoming call or SMS with six digit verification code.
10. In the next page, you'll be asked to put the confirmation code. Input it and you're done.
Please note, this process is mandatory. You won't be able to edit your videos or thumbnail if you fail to complete the above process.
The second step is quite simple.
1. Download YouTube or Update YouTube app from iOS Apple Store or Play Store.
2. Download Creator Studio.
I recommend downloading creator studio app because you will have access to all the features in Desktop app version. One can edit videos with creator studio, edit thumbnail, add video description, add video tags and a lot more. You can also estimate your earnings, traffics like views and communities engaged in your video contents.
3. Download Power director if you did like to edit video pro.
4. You can upload videos from YouTube app itself. Click on the Video camera icon, add description, crop or edit video from the YouTube app itself.