Palate help

I recently got a job as a trainee sommelier as I'm really interested in it. However, I start in 3 weeks and honestly only know the very very basics of wine tasting, serving and wine in general. While I'm listening to podcasts such as Wine For Normal People, reading Wine Folly and watching movies on wine, I cannot for the life of me manage to taste wine properly. I can't seem to pick up anything when smelling either. Are there any tips to improve my palate? Because while I can always memorise theory, it's not much use if I can't do the practical. (However if anyone has any tips on the theory that will also be appreciated.)