I've just replied to your PM but I'll reply here as well rather than leave this open.
I'm pleased you're interested in writing a review for the Must See feature. It's a bit of a hidden secret but just click here and then bookmark that page in your browser. Then just prepare and post your review.
Here are my tips:
In the Subject box write the title of the movie or show. Add a space, colon and a space and where to find the movie or show e.g. Movie Title : Cinema Release or BBC One / Netflix / iPlayer / TalkTalkTV etc
Scroll down a bit and, on the right, add a label or labels for the genre e.g. Sci-Fi, Thriller, Family etc.
The first thing is to post a picture using the Photos icon. Find a high quality picture. The recommended size is 1000 pixels high by 720 pixels wide. Try and find an image with the movie or tv show title. Ensure that any text occupies no more than 80% of the recommended image width because the mobile homepage display does crop the image width and you don't want to see the text cropped. Use a simple photo editor to resize and crop an image to the recommended 1000 x 720 size and to add title text if needed.
Keep the review short and to reflect your enjoyment, critical review or outright disappointment of the movie or TV show. So, you might start with a star rating. Don't include 'spoilers' that might impact on someone's enjoyment but do add hints on what makes the movie or TV show special or different that makes it worth watching. Give an original opinion, maybe with a comparison to other popular movies or shows.
Use Preview, above the composing area, to see what your review will look like. Return to Rich Text to edit until you're happy. If you post and then wish to edit there are three dots for an option menu to the top right of the posted review's message page. Click there and select Edit Message then continue as before.
If you'd like help then just @mention me or Private Message and I'll pop along and give you a helping hand.