Okay - how might LW win the BoB. Unfortunately, we don't have a date to start changing the LW, so I'd go from 1.1.1939.
No Bf 110 that use DB 601 engines - all DB 601 engines that can be spared go to Bf 109 production. This can yield another 1500-2000 Bf 109s by summer of 1940, ie. about doubling the number.
The 109s get the bomb rack facility, so the drop tank fitment is quick and easy ( drop tank was a known thing in Germany well before ww2, the Hs 123 was using it in 1937).
The Bf 109E-1 gets another pair of LMGs in the wing for 6 total; the E-3 and, later, E-4 get a 90 rd drum for the MG FF(M) cannons. See whether the LMG can fire reliably through the prop shaft, so it is 7 LMGs for the E-1, and 3 LMGs + cannons for the E-3 and E-4.
The surplus of 750-1000 fighters needs an increase of pilots' 'production'. Offer good deal to Spanish, Hungarian, Slovakian pilots, but in either way try and get the German training program up to the speed. A much earlier and German-outfitted (no CR.42, but BF 109, etc) Corpo Aereo Italiano might be a good idea, though it will require Germans and Italians being quick on the ball.
Outfitting the bombers with twinned LMG installations might've helped against 'leakers', but the number and quality of escorts is mandatory tool in keeping the bomber losses at acceptable level. Try to have Ju 88 earlier in the game, with a good part of them trimmed down (low-profile ccokpit, only internal bombs, perhaps clip the wings a bit) so they can be faster than per OTL. Similar with Do 17, but that one will not improve much unless better engines are fitted. What is left of Bf 110s perhaps receive Czech HS 12Y engines, so they should be still making 300+ mph with them - these are to be fighter-bombers for low level attacks. Make sure that Avia factory is running at least 2 shifts, and that all Ju 87s have drop tank facility, not just the 87R.
So these are techy things, with a touch on logistics (pilots). Target allocation - kill RAF by killing the Fighter Command in the air; when they don't wan't to come out and play - kill Radars and FC bases.