Changing Axis to Buttons

I got the controller script from the 2D Unity project. And im trying to make it work on Tablets. But my problem is how i make my buttons work when pressed (I want my player to move right if pressed the right one) This is the script, just changed a bit:

 using UnityEngine;
 using System.Collections;
 
 public class PlayerControl : MonoBehaviour
 {
     [HideInInspector]
     public bool facingRight = true;            // For determining which way the player is currently facing.
     [HideInInspector]
     public bool jump = false;                // Condition for whether the player should jump.
 
 
     public float moveForce = 365f;            // Amount of force added to move the player left and right.
     public float maxSpeed = 5f;                // The fastest the player can travel in the x axis.
     public AudioClip[] jumpClips;            // Array of clips for when the player jumps.
     public float jumpForce = 1000f;            // Amount of force added when the player jumps.
     public AudioClip[] taunts;                // Array of clips for when the player taunts.
     public float tauntProbability = 50f;    // Chance of a taunt happening.
     public float tauntDelay = 1f;            // Delay for when the taunt should happen.
 
 
     private int tauntIndex;                    // The index of the taunts array indicating the most recent taunt.
     private Transform groundCheck;            // A position marking where to check if the player is grounded.
     private bool grounded = false;            // Whether or not the player is grounded.
     private Animator anim;                    // Reference to the player's animator component.
 
 
     void Awake()
     {
         // Setting up references.
         groundCheck = transform.Find("groundCheck");
         anim = GetComponent<Animator>();
     }
 
 
     void Update()
     {
         // The player is grounded if a linecast to the groundcheck position hits anything on the ground layer.
         grounded = Physics2D.Linecast(transform.position, groundCheck.position, 1 << LayerMask.NameToLayer("Ground"));  
 
         // If the jump button is pressed and the player is grounded then the player should jump.
 //        if(Input.GetButtonDown("Jump") && grounded)
 //            jump = true;
     }
 
     private bool moveBool;
 
     void FixedUpdate ()
     {
         // Cache the horizontal input.
         float h = Input.GetAxis("Horizontal");
 
         // The Speed animator parameter is set to the absolute value of the horizontal input.
         anim.SetFloat("Speed", Mathf.Abs(h));
 
         // If the player is changing direction (h has a different sign to velocity.x) or hasn't reached maxSpeed yet...
         if(h * rigidbody2D.velocity.x < maxSpeed)
             // ... add a force to the player.
             rigidbody2D.AddForce(Vector2.right * h * moveForce);
 
         // If the player's horizontal velocity is greater than the maxSpeed...
         if(Mathf.Abs(rigidbody2D.velocity.x) > maxSpeed)
             // ... set the player's velocity to the maxSpeed in the x axis.
             rigidbody2D.velocity = new Vector2(Mathf.Sign(rigidbody2D.velocity.x) * maxSpeed, rigidbody2D.velocity.y);
 
         // If the input is moving the player right and the player is facing left...
         if(h > 0 && !facingRight)
             // ... flip the player.
             Flip();
         // Otherwise if the input is moving the player left and the player is facing right...
         else if(h < 0 && facingRight)
             // ... flip the player.
             Flip();
 
         // If the player should jump...
         if(jump)
         {
             // Set the Jump animator trigger parameter.
             anim.SetTrigger("Jump");
 
             // Play a random jump audio clip.
             int i = Random.Range(0, jumpClips.Length);
             AudioSource.PlayClipAtPoint(jumpClips[i], transform.position);
 
             // Add a vertical force to the player.
             rigidbody2D.AddForce(new Vector2(0f, jumpForce));
 
             // Make sure the player can't jump again until the jump conditions from Update are satisfied.
             jump = false;
         }
     }
     
     
     void Flip ()
     {
         // Switch the way the player is labelled as facing.
         facingRight = !facingRight;
 
         // Multiply the player's x local scale by -1.
         Vector3 theScale = transform.localScale;
         theScale.x *= -1;
         transform.localScale = theScale;
     }
 
 
     public IEnumerator Taunt()
     {
         // Check the random chance of taunting.
         float tauntChance = Random.Range(0f, 100f);
         if(tauntChance > tauntProbability)
         {
             // Wait for tauntDelay number of seconds.
             yield return new WaitForSeconds(tauntDelay);
 
             // If there is no clip currently playing.
             if(!audio.isPlaying)
             {
                 // Choose a random, but different taunt.
                 tauntIndex = TauntRandom();
 
                 // Play the new taunt.
                 audio.clip = taunts[tauntIndex];
                 audio.Play();
             }
         }
     }
 
 
     int TauntRandom()
     {
         // Choose a random index of the taunts array.
         int i = Random.Range(0, taunts.Length);
 
         // If it's the same as the previous taunt...
         if(i == tauntIndex)
             // ... try another random taunt.
             return TauntRandom();
         else
             // Otherwise return this index.
             return i;
     }
 
     public GUIStyle jumpStyle;
     public GUIStyle    leftStyle;
     public GUIStyle rightStyle;
             
     void OnGUI (){
         if(GUI.Button(new Rect (Screen.width - 250,Screen.height - 250,200,200), "", jumpStyle) && grounded){
             jump = true;
         }
 
         if(GUI.Button(new Rect (0,Screen.height - 200,200,200), "", leftStyle)){
         }
 
         if(GUI.Button(new Rect (200,Screen.height - 200,200,200), "", rightStyle)){
         }
 
     }
 }

Ive been looking at it for about 1hour and 30mins.. and i still cant find out how.