For me...
-5 c , i'll be wearing a shirt , a fleece jacket , a winter jacket with great wind protection + hood . Fleece scraf would be in my bag and a wool glove.
wool socks with normal converse shoe. LoL....

That would keep me very warm..

Fleece jacket : light weight jacket , keeps u very warm. great for indoor.
Lotion : Vaseline
Gloves : It's not that heavy, bring if u have. If not, go there only buy lo. Not like it's super expensive.

Winter in germany = most of the days rainy & Windy.

you don't need umbrella there.. since the wind is too strong.

hood would be handy ... or a cap or something...

be like russian !
drink a shot of vodka !