UTHs have a sticky side so that they will stick to the underside of your tank, or where ever else you decide to stick them.
If you are VERY careful, it's possible to remove the UTH and use it again. I do it all the time, and it'll still work fine - you just can't go ripping it off..! 
And, I have to put my 2 cents in... 13 IS young. You're younger than the legal working age limit, so you can't really have a job, unless you're babysitting or mowing the lawns, which doesn't always pay as much as you might need for a vet visit or reptile food or reptile care supplies, etc. Also, at 13, you're at an in-between stage of your life - it's called Middle School (yeah, I try to avoid teaching at middle schools because I remember what I was like in middle school...!!). You might be mature for your age, but you're still much more immature than someone who's, say, 23 or 50. And if you're more mature than the average 23 year old, then all I can say is that that is very sad.
As well, at only 13 years of age, it's rather difficult to have as much experience in the reptile business as the average breeder. Check out Ron Tremper, or Marcia at Golden Gate Geckos, or Robin & Russ at R2Reptiles, or Kelli Hammock of HISSS, etc. etc. etc. They've been in the business for YEARS. The latter 4 I learned a great deal from. I've only been in the reptile business for a little over a year - I still consider myself very new in the business, but I draw my information for replies from these trustworthy sources.
Does anyone here remember when any of the above breeders visited this forum? I don't remember Tremper, but I remember when the other 4 were extremely active on these boards. Times have changed.
So, kinik, when people tell you you're young, it's for many reasons. 13 is young. And, yes, you can normally tell from a message about how old a person is - especially if you read how different people write a lot. Don't get insulted by people saying you're young and/or immature - Really, it's NOT something that you can help. You're 13, after all.
~~Dusty
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So Many Alleles, So Little Time...! 


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~~The Gecko Barn~~