Can I replace vanilla extract with lemon extract?

No. Do use a pen or any other writing utensil. If you want to go this route, I suppose you could use a VERY well-cleaned screwdriver, large nail, awl, etc.,...

You could. First, you may want to take a small sample of it and only put it on a little bit of the perfume, so you can try it out.

Use vanilla extract.

Use only one or two drops, depending on how much hot chocolate you're making. Vanilla extract is stronger than some might think, so don't use too much of it.

Fill a glass bottle halfway with fresh, clean lemon zest. Then, fill the other half of the bottle with olive, jojoba, or argan oil. Keep it under the sun for...

Sounds like you might just puree up some mangoes with a little sugar. I would recommend making it only in small batches, because the lemon juice is what keeps it...

Most supermarkets sell it. You can get pure vanilla extract or imitation vanilla extract (which comes in a bigger bottle, and works exactly the same).

Yes, that would be fine, but the scent will be a lot lighter than the real extract.