I have tried modified Hummers method for synthesis of GO. Please refer this article madam.. You will get some information regarding the synthesis of GO by simple method.

The most common method for preparation of GO is Hummer's method or in recent year is a modification the Hummers' method. But simple way you can get GO by treatment graphene (in the case you have graphene growth by simple method, CVD,..)

you can use modified Hummer`s method.you can use this article.I suggest using this article because this method  yields good

You can use Hummer's method lot of articles reported that method.

Mechanochemical exfoliation

I think it depends on how much amount of GO you need. In lab scale preparation, usually a modified Hummer's method is preferred.

If you are willing to establish a simple method for preperation of graphene oxide, I advise you to use different oxidising agents or combination of them to find out the method that gives optimum result.

You can produce  graphene oxide by modified Hummers method followed by sonication. Chemical oxidation and sonication of amorphous carbon material also yields less defective graphene oxide

The most common method for preparation of GO is modified Hummer's method. you can see this my article for detail synthesis. 

http://pubs.rsc.org/en/content/articlelanding/2014/an/c4an01171f

Modified Hummers method

check this article

http://scitation.aip.org/content/aip/journal/apl/98/24/10.1063/1.3599453

Dear Madam,

Simple method for synthesis of GO is modified Hummers method. In this method so many articles are published, try to get good journals and follow one of them. However you can try for novelty in synthesis...

All the Best

It is nice to be eager for simplicity but perfection lies in the details. This reference was entitled as being 'simple'. May be this is not the 'simplest' method you are aiming for, but still seems worth to consider. It is mentioned in case you may have missed, what is always possible with the present flood of graphene related papers:

N. M. Huang, H. N. Lim, C. H. Chia, M. A. Yarmo, and M. R. Muhamad, "Simple room-temperature preparation of high-yield large-area graphene oxide", Int. J. Nanomedicine, Vol. 6, 2011, 3443–3448.

Hi,

Nainggolan ,

If you have the experience of hydrothermal systhesis. The following method might be the simplest way for you to obtain GO:

http://pubs.rsc.org/en/Content/ArticleLanding/2012/JM/c2jm16203b

Hummers method is simplest  and easy method for synthesizing graphene oxide.

check this article

Many modified Hummers method is availaable  and it is one of the way and simplest method to produce large scale GO and rGO's

http://www.rsc.org/suppdata/an/c3/c3an36740a/c3an36740a.pdf

as suggested by most of above Modified Hummers method. simple with high yield.

Very easy way for high quality Graphene Oxide synthesis,

http://instanano.com/nanomaterial-synthesis/carbon-nanomaterial/easy-synthesis-of-high-quality-graphene-oxide-new-method/

@dheeraj kumar Have you tried this method before? and if so did you try filtering graphene oxide from the solution?

Via the Hummers method you can get high quality GO by keeping the temperature below 10°C and working with a teflon reactor. The yield is then about 10%. However, using the Brodie method you get a quantitative yield without taking care of any specific conditions. In addidtion, the purification process is much faster because the delamination has to be triggered by the addition of a base and therefore you can easily filter it before you do the delamination. Moreover, the quality of this Brodie GO is superior to the GO you get from the Hummers method.

See here: Article Brodie or Hummers' -Oxidation conditions determine the struc...