What should i do?

[el_kaeda]

I am a 31 yr old male, finished my grade 8 piano ABRSM exam last year. Grade 6 theory, 2 years ago.
Now currently teaching piano for new beginners.
I find that my sight reading and technique is poor.
Btw i have learned for 10 years already. Just quit piano lesson recently.
I have been using paul harris before and have finished all the books.
What should i do to improve my sight reading further?
How to practice?
Do i need to continue to make the piece perfect to improve sight reading or do i need to read more books?

Thanks

[theholygideons]

Only grade 8 ABRSM?  your repertoire must suck. Expand your repertoire and the sight reading comes naturally.

[stevensk]

Play some easy pieces one or two houres a day and your problem is probably solved after a couple of months. Dont learn the pieces, just play it avista one after another (slowly).

[indianajo]

Buy an old compilation found in a piano bench (Greatest hits of 1951, the 33 by BVC, Amsco Everybody's favorites,  etc) and play through it from front to back. If you don't want to pay antique prices, go to Goodwill/Salvation Army/St Vincent de Paul resale and buy an old piano/organ bench full of music.  
Down load a fake book (the django one is free on line) and learn to play lead sheet and chords, one song after the other.  Formal piano training is all too written down anyway.  fake books is a halfway step to having the guitar player sing a lick to you and you make up a backup track, which is how real keyboard playing that pays money works anyway.  

[hfmadopter]

Buy an old compilation found in a piano bench (Greatest hits of 1951, the 33 by BVC, Amsco Everybody's favorites,  etc) and play through it from front to back. If you don't want to pay antique prices, go to Goodwill/Salvation Army/St Vincent de Paul resale and buy an old piano/organ bench full of music.  
Down load a fake book (the django one is free on line) and learn to play lead sheet and chords, one song after the other.  Formal piano training is all too written down anyway.  fake books is a halfway step to having the guitar player sing a lick to you and you make up a backup track, which is how real keyboard playing that pays money works anyway.  

For gospel and hymns I use lead sheets most recently, it gives a full melody line if you get the good ones ( the main singers line) and you make up your own backing and bass to go with it. You can work up a great sounding piano solo piece of music in just a few passes at it ( especially with a keyboard as you can add instrumentation. People love it). You can make something presentable on the first pass. I've found this to be a quick way to have new material ready for Bible studies etc. Or even visitors. However, it is a bit different from true sight reading of complete pieces of music. For that I suggest backing off in level a bit and do as many as you can. If you are at level 8 and it takes a bit of time to learn a piece then back up to 5 or 6 for sight reading at first. Bet you can do it, then work your way up..