I take it from under my tongue. I find that I'm more likely to get bubbles if I think, "Okay, salivate!" than if I just pick up what's there. I scrape it off my finger onto the edge of the lens, then spread it across.
I can never get a good enough sample first thing in the morning, because my mouth is too dry. What I do is make sure I don't eat or drink during my last hour at work, then collect the sample first thing when I get home. If I've had an afternoon snack, then I rinse my mouth before beginning that last hour.
If the dried sample looks completely blank, your saliva is too thin. Try again at a time when you haven't been drinking so much water. If it looks really crowded and complicated, your saliva is too thick. Next time take just a little sip of water first. The crowded look also can mean the saliva is pooling in the middle of the lens. Keep an eye on it while it's drying to see if this is happening (if the edges dry quickly but the middle is still wet after 15 minutes) and if so, tilt it until it's dry.
Those are my tips after 5 months of use. I think it's working right....
Mama to a boy EnviroKid
10 years old and a little girl EnviroBaby
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