If you are using '''Wordpress''' you install the Beds24 Wordpress plugin. This will allow you to easily install widgets using shortcodes.
Note:
Your website CSS (e.g. Wordpress theme CSS) might override the CSS for the booking widgets.
To fix display problems with of the booking strip try adding
.b24bookingstrip select{width: auto;}
to the custom CSS of your Wordpress page.
Best regards, Annette