Procedure to upgrade release of hika

Since june I have been using hika business and i am very happy about that.
I am customizating a little bit the css and some views.

I know you are going to provider a new release in august.
What is the right procedure to install the new release and don't lose my customizations?

Thanks.

Thank you jerome
To modify the CSS I use the hikashop backend, so I should be on safe.

How could i understand if you made some modification in the standard frontend css and in the standard views?
Is there a sort of documentation in order to understand if you modify that part?
This because I don't want to lose any modification or enhancement you can provide.

Thank you in advance.

Thanks nicolas

Yes I am doing all my customization via Hika's interface.

My question is a little bit different, sorry for my english, i will try to explain it another time.

I use a custom Front-end CSS file (frontend_custom.css).
Inside this file I changed a little bit some options:

.hikashop_product_left_part{
text-align:center;
float:left;
/* Stefano Start */
/* width:50%; */
width:35%;
margin-bottom:20px;
/* Stefano End */
}

Now, when you release a new version of Hika, how may I know if you changed something in the default frontend.CSS
For example if you change the allignment in the .hikashop_product_left_part
.hikashop_product_left_part{
text-align:center;
float:RIGHT;
}

The same thing is for the custom views.

Do you send a list of the files you changed or is necessary to verify them manually?

I can manually check everything because the customizations are really few for the moment, but I would like to know if exist a smarter way to do that.

Thank You.

Thanks.