How to Use an STP: Position, Drainage, and Practice
An STP needs the collection cup positioned correctly and the outlet angled so urine can drain. Practice at home before using it in a public bathroom. Start somewhere a leak is easy to clean, such as the shower.
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Find the position without clothing in the way
Follow the device's instructions for placing the cup around the urethral opening. Hold it with the amount of pressure specified; pressing harder can distort some designs rather than improve the fit.
Check that the outlet points toward the drain or toilet and is not compressed. The urine needs a clear path out of the cup.
Watch what happens and adjust one thing
Let urine flow without straining. If the cup fills faster than it drains or leaks at the edge, stop the attempt and reassess position and angle. Do not assume a leak means you need to press harder.
A device may need a different position on different bodies. There is no fixed number of practice attempts that works for everyone.
Add your usual clothes
Once you are comfortable without obstructions, practice with the underwear and trousers you intend to wear. Fabric can squeeze the outlet or move the cup. Check access through the fly and how you will drain residual liquid before putting the device away.
Clean and dry it as directed. Pay attention to the channel, and wash any support garments separately according to their care labels.
If repeated leaks remain, check for a compressed outlet or a cup that cannot sit comfortably against your body. The STP buying guide covers fit differences if you are considering another design.