Adding "Authorization" header in get request

@niallr son this is my code

Hi guys, I need your help
I got this code example around, I dont remenber
I dont know if this code is good

service-provider.ts

export class ServiceProvider {

  api: string = 'https://www.mydomine/api/v1/';
  isLoggedIn = false;
  AuthToken: string;

  constructor(public http: Http) {
    this.isLoggedIn = false;
    this.AuthToken = null;
  }

  // Authenticate and verify email and password of User and create TOKEN
  authenticate(user) {
    let creds = 'email=' + user.email + "&password=" + user.password;
    let headers = new Headers();
    headers.append('Content-Type', 'application/x-www-form-urlencoded');

    return new Promise(resolve => {
        this.http.post(this.api+'auth', creds, {headers: headers}).subscribe( data => {
            if(data.json().success){
                this.storeUserCredentials(data.json().success);
                resolve(true);
            }
            else
                resolve(false);
        });
    });
  }

  // Get the token and send to userCredentials method bellow
  storeUserCredentials(token) {
    window.localStorage.setItem('token', token);
    this.useCredentials(token);
  }

  useCredentials(token) {
    this.isLoggedIn = true;
    this.AuthToken = token;
  }

  loadUserCredentials() {
    let token = window.localStorage.getItem('token');
    this.useCredentials(token);
  }

  // Destroy Authentication of User
  destroyUserCredentials() {
      this.isLoggedIn = false;
      this.AuthToken = null;
      window.localStorage.clear();
  }

  createAuthorization(headers: Headers) {
    headers.append('Authorization', window.localStorage.getItem('token'));
  }

  getCauses() {
    return this.http.get(this.api+'causes').map( res => res.json());
  }

}

I'm doing login and get the token of my API, but I dont know to use TOKEN in other places, for example in getCauses method
I want resolve by steps
1 - To use TOKEN in others requests using Headers Authorization + Beares + Token
2 - To use TOKEN to call forever user logged in all pages