Sometime am at a lost...about Imaan and Yakeen

Question

Assalam...
From a Tablighi man...
Sometime am at a lost...about Imaan and Yakeen
Imaan is to believe which is quite easy to explain and understand.
What is Yakeen... a complete belief in Allah's Siffaat.. all his names and everything we can understand from that.
Allah does everything and Creatures does nothing except with the help of Allah...
How do we apply this understanding of Yakeen in our daily life...
Hope you got the point - please elaborate