First I receive the briefing, then I execute the benchmark to get insights and ideas that would improve the ecommerce.

After the benchmark I do the heuristic evaluation to identify ecommerce usability mistakes from an expert point of view. Then, I collect data using an  excel sheet.
Besides doing heuristic evaluation, I build the user persona in order to identify the users in the application and priorize them. It is done with the illustrator tool.
After considering the user persona I think about the customer journey to understand the user process of buying using post its.
The next step is to do remote test using Lookback tool aiming at identify the real user problems with the ecommerce. At the same time I do face to face  user test to detect ecommerce mistakes what can allow to get a solution.
After doing user tests I make the wireflow to visualize the navigation among interfaces in the ecommerce. I draw each interface with pen and paper and after that, I stick them in illustrator tool.  
Besides doing the wireflows, I do the low-fi prototypes to see the visual structure of each interface in the beginning phase with adobe XD
After I do the wireframes, I think about the branding of the ecommerce using adobe XD.
Finally I put it in high-fi prototypes using adobe XD to get the real app aesthetic
I learned that when I have a limit time it is necessary to do it only the most important methods that gives value for the project.
Besides I see that sometimes you have to change your business strategy if you want to elevate your branding.