A really good oil is a must! I've run into really bad stuff that I couldn't swallow, so maybe if you try different brands until you find the one right for you?
I wasn't sure I'd be able to take the olive oil either, but I've flushed 3 times and haven't had any problem. I measure the oil into a glass, then squeeze the juice from two ruby red grapefruit (by hand) into a bowl, remove any seeds and pulp, then pour it into the glass of oil. I then use my hand blender and mix it thoroughly. Then I drink it straight down. It's just *thick* grapefruit juice! There is a bit of aftertaste, which I get rid of by swishing tomato juice in my mouth (I spit it back out).
I have a strong gag reflex and I really dreaded it the first time, but I soon learned it was really 'in my mind' and wasn't bad at all. Now the Epson Salts is what gets me! But I've learned to mix that with grapefruit juce too and get it very cold. While I can get it down, it's still not wonderful .
Just don't give up! There are probably several ways to taylor it to suit you, you just need to find which it is! Good luck.