How do I make a jpeg image small enough to upload?

[slowmotion]

I'm sure this has been explained before, but I just can't find the answer using the search function. I apologise.
My photos are in My Pictures on an XP machine. They are usually about 3.2 Mb in size. If I try and use the Upload a File button to add them into a post I get told that the file is too big. How do I shrink them? Words of one syllable please. I'm not that savvy.

Thank you.

 

[slowmotion]

Thanks MP. If I right click I get three choices....

Windows Picture and Fax Viewer
Paint
Internet Explorer

There are other options but none looks like a goer. I'm stumped

 

[ianrauk]

in paint,
use sketch/skew or resize and reduce to 25%
save as

 

[slowmotion]

Thank you both. Alas, I have no Picture Manager that I can find. The Paint route worked.

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