For whatever reason you need a Bidet, this works quite well.
Use a clean small Coke bottle. Drill a small hole just below the cap ridge on the side of the bottle.
Fill the bottle with water at whatever temperature your supposed to use. You can also put whatever wash such as Betadine that your Doctor requires. Place the cap firmly back on once filled.
Once your business is done, use the bottle upside down and squeeze to aim at the appropriate spot. The steam can be easily aimed upwards so you can remain seated on the toilet.
For those that cannot use Toilet Paper due to allergies or for whatever reason, just bring the prepared bottle with you when on the road. Fill at a sink and take with you to the john.