Due to Engineering work all weekend there are no tube trains from Paddington via Kensington to Tower Hill, or from Earls Court to Embankment.
From Paddington use the via Kings Cross Circle line to Tower Hill (that is the 'wrong way' round the Circle).
From Heathrow continue on the Piccadilly into central London and switch lines at the appropriate stations.
Or use local bus routes. Being Central London there is no need for rail replacement buses.