Difference between 实际, 现实, 确实, and 实在 These 4 words (实际, 现实, 确实, and 实在) all mean different combinations of 'real', 'indeed', 'practical', 'really', and 'reality'. Is there any easy way to distinguish, remember and understand the differences between these 4 words? Thank you!
I'm going to try and make this as clear and simple as I can:

实际：practical/actual(ality)
实际上："in fact,...."
很实际：very practical

现实：real/reality
现实生活中：in real life
成为现实：to be realized

确实：indeed/really 
确实好：it really is good

实在：really/honestly/truly
实在对不起：truly sorry
这个人很实在：he's really down to earth 

As far as remembering I would highly suggest you understand what each individual character means...most Chinese words are compounds (two words put together) - for instance if we look at 确实 we have: (确 certain + 实 substantial = verified to be true, indeed). This kind of understanding will give you a huge advantage to learning Chinese.