I'm sorry it's so late. I had actually forgotten about this for a short time.. I'll get back up to speed soon! I promise!
Sa さ As seen, it can also be written that way. It can be used in texts mainly. It can be used and written either way.
shi し This is very simple. How it can be memorized it 'SHI has pretty hair'
Su す I remember this as a pig's tail. 'Suuuuuuu wee!'
Se せ This one, 'Please SEt the table' REMEMBER THIS ONE. Sa in Katakana is VERY VERY similar.
So そ This one was difficult to remember for me. 'SO done with this language'
Look! Another SEt of five! Notice what I did there? No? okay. Keep studying!