Changing Transform.Rotate to LocalRotation

hi, I'm new to unity coding and i have a problem
i want to rotate my object with mouse but everything works perfect but its rotating on a wrong anchor, and as i think i should change the rotate to Transform.LocalRotation, I've search the google but i couldn't find my answer, can you please help me to make it work fine
really appreciate it

Here is my code:

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3.  
4. public class DragRotateSlowdownLocal : MonoBehaviour {
5.    
6.     public float rotationSpeed = 10.0F;
7.     public float lerpSpeed = 1.0F;
8.    
9.     private Vector3 theSpeed;
10.     private Vector3 avgSpeed;
11.     private bool isDragging = false;
12.     private Vector3 targetSpeedX;
13.    
14.     void OnPress() {
15.        
16.         isDragging = true;
17.     }
18.    
19.     void Update() {
20.  
21.        
22.         if (Input.touchCount > 0 && isDragging) {
23.             theSpeed = new Vector3(-Input.touches[0].deltaPosition.x, Input.touches[0].deltaPosition.y, 0.0F);
24.             avgSpeed = Vector3.Lerp(avgSpeed, theSpeed, Time.deltaTime * 5);
25.         } else {
26.             if (isDragging) {
27.                 theSpeed = avgSpeed;
28.                 isDragging = false;
29.             }
30.             float i = Time.deltaTime * lerpSpeed;
31.             theSpeed = Vector3.Lerp(theSpeed, Vector3.zero, i);
32.         }
33.        
34.         transform.Rotate(Camera.main.transform.up * theSpeed.x * rotationSpeed, Space.World);
35.         //transform.Rotate(Camera.main.transform.right * theSpeed.y * rotationSpeed, Space.World);
36.     }
37. }