With so many different types of products on the marketplace there are many different approaches you can take. Checking your clothes periodically for signs of damage (rather than leaving them for long periods of time undisturbed) remains an indispensable way of ensuring longevity for your clothes.
Moth Traps - These work on the principle of attracting male moths by recreating the female sex pheromone and attracting the males moths to a sticky pad which stops them reproducing. They are marketed both as 'traps' and 'monitors' - in a sense both are true. They do trap male moths but for the largest users of these products such as stately homes with priceless fabric collections they are also there to provide an alert to an increase in moths and/or a possible infestation.
Natural Moth Repellents - The thought process behind any natural moth repellent from lavender bags to cedar blocks to products with more complicated formulations like Colibri - is that in nature there are some plants which work hard to discourage insect attack. The use of products like Lavender and Cedar has continued because of observed experience combined with folklore - your grandparents would have put away woollens with fragrance sachets because that is something they may have been taught by her own grandparents. So while your ancestors couldn't have offered many tips on using an iPhone they did wear clothes and as clothes were expensive they wanted to look after them. Elizabeth I was reported to have put perfume, rose-water and cloves amongst the royal chests - whether this was an early attempt at a moth repellent or not, the earliest recorded 'recipes' on how to banish these pests are over 500 years old.
Natural repellents try and recreate the same conditions which discourage insects with the use of products which are observed to discourage moths (such as cedar blocks) or a range of naturally derived essential oils from plants and trees which are unattractive to insects.
The range of Colibri products are made with a range of 15 essential oils in addition to a primary fragrance (lavender, cedar or lemongrass) some people do wonder which is more effective. Given that the olfactory systems of moths enable some species of male moths to smell a female from many miles away we are dealing with a sense of smell that is immeasurably more powerful than our own. The combination of different essential oils is just as important in the products effectiveness as the exact proportions of each essential oil. Consider that while you might not be able to detect the lavender oil because its masked by a far higher concentration of cedar oil the moth will be far more attuned to the various components. So you should really choose a primary fragrance that you like as it will permeate your clothing, no one wants open their wardrobe and be overpowered by the pong of mothballs, equally some people don't like lavender so pick something you like. Some people are unconvinced about the efficacy of something natural compared to a chemical repellent and I'm respectful of their view just as some people won't believe in the benefits of meditation or yoga for their health. I first began selling Colibri based on feedback from customers at my parents dry cleaning business who had been very impressed with it - which helped me overcome my own lack of experience with the power of plants and their essential oils. The wisest approach is to test and make your decision based on your own observations.
Chemical Moth Products
Moth Balls - With a distinctive smell these were once made from napthalene (banned in the EU in 2008) and more recently PDCD (para-dichlorobenzene). They have been associated with cancer risk and organ damage.
The most popular synthetic repellents and moth killers in use today are chemicals such are pyrethrin, permethrin and transflurin. These will work to kill the adult moth or to kill the larvae.
They all come with various health warnings, dire warnings of damage to marine life and extensive safety data sheets. While I don't doubt the effectiveness of some of these products, personally I choose not to sell them because of the potential for health risks.