Indeed a good question ...
I clicked on my "Signed in as elephant" link and found that we have "announcements" under our profiles, and so I created one"
Not sure whether this is the Blog style you meant ...
I also tested Peter's link to his details since he said he had a blog, but he had no "announcements".
So I then checked my profile, and yes there is a "blog" field there, but I suspect it is meant to contain an http: internet link to your blog that is external to Beoworld.
So if you already have a blog, edit your profile and put its address there.
If you dont have a blog and want one, the look at varioys free blog sites to find one that appeals to you in terms of its look and feel, sign up, and the populate your profile.
In the past I have used https://www.blogger.com/start because it is accessible from my gmail (google mail) sign-on but the use of gmail is not a prerequisite
First B&O (1976) was a Beogram 1500 ... latest (2011) change has been to couple the BL11 with the BL6Ks *sounds superb*