DIY

Sorry I just wrote in Chinese and for some reason it did not work. SO I am writing in English now to share my experience.

I have got rid of skin tags twice: 

the first time it was on the right temple. I used floss to tie it every night, I also used white vinegar. during the day time I untied it as I had to go out of
the house. In about three days, I used a nail clipper and it came off easily. by then the skin colour  had changed and it looked dead.

the second time, there was one on my upper body. this time I tied it again with dental floss but without using the vinegar and I did not take the floss off because it did not affect my going out.  in a couple of days time I got rid of it with the nail clipper again. 

if it is still painful when you try to cut it it means it is still 'live' and you need to wait a bit longer. when it is dead then it is very easy to remove it.  there is no mark afterwards.