Suggestion:

I Have Decided to Start Keeping a Diary in English

The 9th of December, 2015. 

Today, my mother finally went to the hairdresser's to get her hair done. I don't understand this next bit. She is a devout Christian and a lover of traditional European oil paintings. Have you ever seen an old European oil painting before? Do you remember the little angels in those paintings? Well, my mother loves how they look and wanted to get her hair cut in a similar style.

However, when she got back home I was shocked. Her hair was awful. It looked cheap and tacky. I helped her fix it, but it wasn't it easy. I think that hairdresser's and barber's should have to be tested before being allowed to work professionally in China. It's not right that people who haven't the faintest clue about how to cut hair are allowed to ruin people's hair like my mum's. 

That's all I have to say today. Thanks for reading it! Please give me some advice if you have time!

理发店 - This translates as both "barber shop" and "hairdresser's". Men go to the barber's, while women go to the hairdresser's

发型 - hairstyle

虔诚 - devout

When you use 但是 as the first word of a paragrah you should write "however"

忠告 - to advise (动词) / advice (名词) - advice is an uncountable noun!

I'm beginning to keep an English diary here

Dec.9 Smog

Today my mother finally went to the hairdresser to have a new perm. barbershop to do her hair in order to consume my perm which soon would close to expiration. She is a loyal Christian and fond of those adorable angels who belong to the medieval traditional European oil paintings. That was the reason why she wanted her hair to look  seems like an angels', short and a natural curl, just like Mia Farrow's hair cut in 'Rosemary's.Baby' of 1968'.

But when she returned back home, the her hair was just like  a bombed had hit it, or something which looks so cheap and in poor taste. I knew it! I  finally helped her fix that it. after all, but I do think that Chinese hairdressers/hair stylists barbers don't have any artistic ability/creativity/ expertise high aesthetics expect except those shops which charge you more than 1000 Yuan. I really think that Chinese hairdresser's qualification barbers' licenses should require an associate degree or something equal as to that. They should study on those Renaissance statues' hair instead of making people's hair just like bar girls.

All for today's diary, hope I could keep this up. Thanks for reading it, please give me some advises on language only if you have time.

I'm beginning to keep an English diary here

Dec.9 Smog

Today my mother finally went to the barbershop to do her hair in order to consume my perm which soon would close to expiration. She is a loyal christian and fond of those adorable angels who belong to the medieval traditional European oil paintings. That was the reason why she wanted her hair seems like angels, short and natural curl, just like Mia Farrow's hair cut in 'Rosemary's.Baby.1968'.

But when she back home, the hair was just like bombed or something which looks so cheap and poor taste. I knew it... I helped her fix that after all, but I do think that Chinese barbers don't have high aesthetics expect those shops which charge you more than 1000 Yuan. I really think that Chinese barbers' licenses should require associate degree or something equal as that. They should study on those Renaissance statues' hair instead of making people's hair just like bar girls.
Sorry, I did not see the last bit at the end.
That's all for today's diary, hope I can could keep this up. Thanks for reading it, please give me some advice on language only if you have time.