A way to start Dorico with my Logo

Whats is the best way to start Dorico with my Log on master page and my master diagram?Can i save it on defaults?

No. You’d need to save a blank file, and open that file to launch Dorico.

I always start from my default file, which has master pages set up for all the page sizes I commonly use, and relevant info at the bottom. (It’s a lot faster to delete something not needed, than to create something needed.) You could easily set up a default file that has your graphic logo saved on different master pages, and always start from that file.

Yep. I don’t think I’ve used the “New File” option in over two years…

Consider that master page sets can now be imported and exported. There’s a potential time-saving there, dependent on what you’re doing.