Here's a link to the full series of 5 Altberg bootcare videos
http://www.walkingforum.co.uk/index.php?topic=42955.0Altberg's main customer base are the squaddies based at Catterick Army camp just down the road which is who I think these videos are primarily aimed at. Being critical I would suggest his approach is a little slapdash and apart from missing half the boot the basics are all there.
There's a fine line between applying too much or too little wax. Too much wax and you either end up with the wax sitting on the surface of the leather turning white then peeling and cracking off or worse a horrible sticky mess that ends up turning your boots into very powerful dust magnets. Too little wax and your boots will not remain water repellent for very long allowing any water to soak down into the fibres of the leather.
Always start with a clean boot it's no good trying to wax dirty boots. The mud, dirt and animal crap damages the fibres of the leather shortening the life of the boots and needs to be removed. I've found Nikwax Footwear Cleaning Gel to be an excellent product for this purpose.
I apply the wax using my finger end (the heat from it actually helps) and apply it in several thin layers working each layer well into the leather by hand and then brushing it to drive the oils contained within the wax down into the fibres of the leather to make it supple. Applying thin layers are much easier to work into the leather than one thick layer. Allow some time for the oils to soak in and the wax to set/skin over. Once it feels dry to the touch and has hazed over buff them with a brush to what ever finish you prefer.
Here's an old post and you won't go far wrong following the advice contained in the Whalley Warm & Dry bootcare leaflet
http://www.walkingforum.co.uk/index.php?topic=39039.msg555671#msg555671My preferred waxes are a combination of the Cherry Blossom Waxed Leather Oil for the high wear areas of the boot and the Grangers G-Wax for all over use. An occasional coat of a decent leather conditioner such as Grangers can also help.
Personally I find the Leder Gris is just too temperature dependent and can be really difficult to apply if it's not soft enough. It also tends to dry out, harden and evaporate over time and the oils in the Leder Gris Xtreme can turn rancid and smell really bad after a while. The problem with both products could easily be resolved if Altberg replaced the non-airtight tins they sell it in with airtight screw top jars like the majority of other waxes on the market are sold in.