HTML

mat-form date pickerwith hints

<mat-form-field appearance="fill">
  <mat-label>Choose a date</mat-label>
  <input matInput [matDatepicker]="picker">
  <mat-hint>MM/DD/YYYY</mat-hint>
  <mat-datepicker-toggle matSuffix [for]="picker"></mat-datepicker-toggle>
  <mat-datepicker #picker></mat-datepicker>
</mat-form-field>