To melt ice you need heat, like an hair drier or a stove.
Unfortunately, melting all the ice stored at the Poles is not something you achieve with an hair drier, unless you have a very large hair drier.
One of the biggest and easily accessible heat source we have available is few kilometers under our feet: the Earth mantle.
If you manage to trigger massive volcanic eruptions under the Poles, the heat coming from the lava will melt the ice caps, as it already happened on a smaller scale in Iceland
A jökulhlaup (Icelandic pronunciation: [ˈjœːkʏl̥øip]) (literally "glacial run") is a type of glacial outburst flood. It is an Icelandic term that has been adopted in glaciological terminology in many languages. It originally referred to the well-known subglacial outburst floods from Vatnajökull, Iceland, which are triggered by geothermal heating and occasionally by a volcanic subglacial eruption, but it is now used to describe any large and abrupt release of water from a subglacial or proglacial lake/reservoir.
On a side note, the massive volcanic eruptions would also slightly rise the sea floor level, pushing further up the water level, and also fill the atmosphere with ashes and dust, shielding solar radiation.
Though the latter may actually freeze back the waters on the medium term, for sure it will make the planet unlivable, which is your goal.