/w/ is a labio-velar approximant/semi-vowel. The lips are rounded and the tongue is in the position for a back close mid / close vowel.
The pronunciation of the approximant /r/varies considerably. in BrE RP, it is a post-alveolar approximant, IPA [ɹ]. It may also be rendered as an alveolar tap [ɾ]; in other vaieties it can be a lingual trill [r], an uvular trill [ʀ] or an uvular fricative [ʁ]. It can also be [ʈ], aimilar to [ɹ], but with more reroflexion.