No "Preferences"

[berlinick]

Got it! Thank you

[berlinick]

"Settings > xfce4 Settings Manager > Keyboard"

It turns out, I did it already before the original post, when I turned on the very option to have the Russian layout. It adds the layout to the keyboard, but doesn't show the current layout on the panel and doesn't let you change it.
However, without this instruction it makes no sense to look for how to include the layout indicator to the panel

Thank you for the hint!

[berlinick]

For keyboard layouts under XFCE:

Right-click on the top or bottom panel and select "add new item". Then look for "Keyboard Layouts". This should display a small US flag indicating that you are using English Layout. Right-click on the flag -> Properties and then Add would give you a list of choices for languages and keyboards.

If the Keyboard Layout applet is not on the list, you can install it via synaptic, look for xfce4-xkb-plugin, or type in terminal:

sudo apt-get install xfce4-xkb-plugin

or install xfce4-goodies

sudo apt-get install xfce4-goodies

which comes with a lot of nice xfce stuff.

I did it through the panel. Worked perfectly.
Lot's of other pleasant things there I'll check them out first. Next thing - goodies