Now I've been doing this hobby for a while and I've tried many different types of walking clothing to suit all weather and all terrain. I've written this piece to hopefully impart some advice on what works well and what not so well.
There's such a huge range of things to think about when choosing the type of walking clothing, but in the main these mostly fit into the following categories: Boots, Jackets, Mid Layers, Base Layers, Trousers, Backpacks and Accessories.
I would always suggest getting a decent pair of waterproof boots which offer good ankle support and are lightweight. Traditionally boots used to be all leather but nowadays you can get many types of suede and fabric boots which offer the same level of waterproof protection as leather.
Before going out on that first long trek always make sure you've adequately broken in your boots with shorter walks. Ensure the boots aren't pinching your feet and that they are not causing any blisters.
You could go crazy with all the different choices of hiking jackets and go from the smaller jackets which pack away into a pocket up to the uber-padded warm winter jackets. I personally prefer a good lightweight waterproof which has the option to zip in a mid layer / fleece if it gets cold with a peaked hood to keep the rain out of your eyes.
The key with walking clothing is layers. Layers can make all the difference between getting too hot or too cold. Fleeces are a good mid layer option. Although you can get thick fleeces which are quite bulky and warm, there are quite a few micro fleeces on the market which are more lightweight but equally as warm. Having a micro fleece is more preferable as it's less to pack and carry in your backpack.
A base layer is the item of walking clothing which is closest to your skin. With this in mind it is not advisable to wear a cotton garment. This is because cotton absorbs moisture and will get heavy and will make you cold. A poly-type base layers will wick the moisture away from your body leaving you feeling comfortable.
As with base layers, you want to avoid heavy trousers and opt for a more lightweight (you see the theme here - lightweight!) and quick drying material. I normally opt for the type of trousers which have the option to zip off at the knee so they double up as shorts, allowing you to be prepared for those days when it's sunny when you set off but rainy by the time you're half way through your walk.
Backpacks can come in may sizes to cater for the short walks to the major treks. I've got a range of daypacks and backpacks because I'm out on the hills every other weekend, but for people starting out I'd suggest investing in a medium size pack which will fit some spare dry kit and enough provisions for the day (water, energy bars, flask of coffee etc.).
I would recommend a backpack which has ample padding on the straps and a waist belt to spread the load evenly. Most backpacks also come with an option for holding a water pouch which can be a great space saver and easy to take on board fluids whilst on the move.
There are a range of accessories which are helpful for regular hikers and first-timers alike. I'm not going to 'ramble on' (pardon the pun!), but some things you should consider are: Gaiters, Waterproof Over-Trousers, Walking Poles, Woolly Hat, Sun Hat, Compass, Gloves and a Torch.
I hope this advice on walking clothing has been of help and please feel free to leave me a comment in the section below.