Schema::create('posts', function (Blueprint  $table) {
    $table->uuid(); // you can also custom your uuid `uuid('post_uuid')`
    $table->string('title');
    $table->string('body');
    $table->timestamps();
});

use WithUuid trait in your Model and declare the primary key

Example:

namespace App;

use Rollswan\Uuid\Traits\WithUuid;
use Illuminate\Database\Eloquent\Model;

class Post extends Model
{
    use WithUuid;
    protected $primaryKey = 'uuid';
}

Done! This will automatically generate unique UUID whenever you save a new record.