I use CCleaner also.
But I also have my only personal policy about downloads and installs. I limit such activities to "needs" versus "like to haves".
Not always easy as there are some really interesting tools, utilities, etc.. to be found.
However, once I have finished testing I immediately uninstall and/or delete as applicable.
And I tend to squirrel away .pdf tutorials, white papers, diagrams and such to read later on. Which may or may not happen
All are saved in a designated folder that can be deleted without worry that some important file will be lost.
Keeping the drive "clean as you go", at least as best you can sans the leftover junk that does accumulate can be a big help.
Always get a bit uneasy during large...