Pretty broad question. One thing I suggest: Do not keep downloads in your home directory. Keep them in a directory under /tmp. This avoids accumulation of download clutter.
Sure I could do it in the download folder directly as well, but in reality I had to go through 100s of files every few months which can be annoying.
I wrote about it a few years ago here and I do it still http://jontelang.com/blog/2015/08/17/hazel-is-great.html
set -eu
AGE_LIMIT=$(( `date +%s` - (14 * 86400) ))
for FILE in ~/Downloads/*
do
if [ -e "$FILE" ]
then
export `stat -s "$FILE"`
if [ $st_birthtime -lt $AGE_LIMIT ]
then
mv "$FILE" "~/Needing review/"
fi
fi
done
find ~/Downloads -Btime +14d -exec mv {} ~/Needing\ review \;
There are no good Windows equivalents.
I wish I had enough programming knowledge to write a truly cross-platform equivalent.
This is a serious itch I'd like to scratch.