<apex:form id="theform">
    Name <apex:inputText value="{!name}" id="name" label="Fisrt Name"  /><br />
    Phone <apex:inputText value="{!phone}" id="phone" label="Last Name" /><br />
    Website <apex:inputText value="{!website}" id="website" label="website" /><br />
    <apex:inputFile value="{!attachment1.body}" filename="{!attachment1.Name}" id="theAttachment" accept="image/jpeg,image/jpg, image/png, application/pdf, application/rtf, image/gif, image/bmp, image/tiff, image/tif, application/vnd.oasis.opendocument.text, application/msword,application/vnd.openxmlformats-officedocument.wordprocessingml.document" filesize="{!att0size}" />
    <apex:commandButton value="Upload" action="{!sendJSON}" styleClass="btn btn-primary" />
</apex:form>

public void sendJSON(){

    String encodedBody = EncodingUtil.base64Encode(attachment1.Body);
    String requestUrl;
    requestUrl = 'https://xxxxx-developer-edition.ap1.force.com/services/apexrest/Account/';
    String Body;
    Body = '{"name" : "' + name + '","phone" : "' + phone + '","website" : "' + website + '","fileUploadName" : " ' + attachment1.Name + '","fileUploadBody" : "' + attachment1.Body + '"}';
    system.debug('!!! apiform: ' + Body);

    Http h = new Http();
    HttpRequest req = new HttpRequest();
    HttpResponse res=new HttpResponse();
    req.setTimeout(120000);
    req.setEndpoint(requestUrl);
    req.setHeader('Content-Type','application/json');//Set the Proper Header
    req.setHeader('Accept','application/json');
    req.setBody(Body);//JSON body as String
    req.setMethod('POST');

    try{
        res=h.send(req);

        finalJSON2 = res.getBody();
        system.debug('!! ' + res.getBody());
        system.debug('!! getStatusCode ' + res.getStatusCode());
        if(res.getStatusCode() != 201 && res.getStatusCode() != 200 ){
            finalJSON2 = 'error != to 200's: ' + String.valueOf(res.getStatusCode());
            //log the error
        }else{
            finalJSON2 = res.getBody();
        }

    }catch (Exception e){
        finalJSON2 = 'Error !!! ' + e;
    }
    //return res.getBody();
}

@HttpPost
global static String doPost(String phone, String website, String other, String name, String fileUploadName, String fileUploadBody) {
    Account account = new Account();
    account.Name = name;
    account.phone = phone;
    account.website = website;
    insert account;

    Attachment attachment1 = new Attachment();
    attachment1.ParentId = account.Id;
    attachment1.Body = Blob.valueOf(fileUploadBody);
    attachment1.Name = fileUploadName;

    system.debug('!!! ' + fileUploadBody); // debug: {Body=Blob[49616], Name=lead tab.jpg}
    insert attachment1;
    return account.Id;
}