I hope I can try to answer some of your questions, I work at a salon where I apply hair extensions and Ive also had them. So I can try to give you as much feedback as possible.

 

1) how long does your own hair have to be, well if you would like strand by strand then at least 3 inches. Anything shorter might look to odd and might be difficult to blend especially if you would like to go very long.

I think when hair is that short mayb using wefts might be a better alternative. Another advantage of using hair wefts is that they are cheaper.

2) in terms of the least damaging, it really all depends on who is doing your extensions. I have seen some bad work out there, and its coming not from one method but all kinds:tapes, fusion, rings etc. So there is no one answer for this question. Just make sure you find an experienced person, who guarantees their work, and most importantly , follow their advice.

 

3) The reason why we recommend that you should not have them in longer than 3 months is because your hair grows about half an inch each month, so by the third month your extension would have moved almost two inches from the scalp. This adds a lot of tension to your own hair. Think of it like a back pack or heavy purse. If its on your shoulder it hurts less, and is less stressful to your back then if you hold it in your hand, which is further away. The same can be said for your hair. The further away from the scalp the more heavy it becomes, and the more your chances increase for breakage and damage.

 

I hope this is helpful, I know there are some really great hair extension artists on this forum, maybe then add something I have missed. But good luck and post your pictures when you get your new fab hair!