Picture size - large or small how to

Hi folks, just wondering how some posters can post small pictures on there posts but when i post it shows large pictures.
Also with samsung tablet how do you reduce size as sometimes it says that content is to large to post? I have tried every thing but cannot seem to reduce size. Not computer literate enough i guess.
Would love to be able to just post small pictures , ie like the one goldgasm posted in his post. Cheers and thanks.

Hi Travelergold
I just open the pic with paint or whatever editing program you have and click on resize,then type in say 25% and save it.

Cheers deutran, will try that and see how we go.

Go to playstore on your tablet, type in "image resizer" find an image resizer app that you like. Install it and start playing.