how to write a letter as a spouse for the uk settlement (wife) visa?

hi there ,

im applying a spouse visa in hong kong to join my husband in the uk.
however, my husband said that i have to write a letter as an applicant. i do not know what to put into the letter, how do i start the letter? i did some reseach, but i couldnt find any letter that is written by the applicant? i only found the letter written by the sponsor.

can anyone please tell me what to put in? for example, do i write about how we have met, and my working status, etc?

i would be very thankful for your reply!