TheBigBoy is being flippant, but he's right.
Asset Spam is not something that requires a particularly 'strategy' to play against. For most decks, either you trash everything (or almost everything), or you lose at some point in the (sometimes quite distant) future. Sometimes you can leave things like PAD Campaign running, but even those really need to go or you risk losing the economic war.
Typically you need to identify the most important things to trash - Political Assets (Sensie in particular), win conditions (SanSan, Jeeves, BioEthics), recursion (Team Sponsorship), econ (Temples) is a rough order to go for, but sometimes it's more important to trash econ than SanSan (e.g. if the corp is broke or you have R&D lock).
But order aside, you still need to trash everything. Ultimately this is very hard because it costs a lot, and there are frequently other threats to deal with at the same time (Breaking News plays, random Psychic Fields, HHN). Andy is fast enough against a lot of decks to do it, but not all, and sometimes a bad start (or a good corp start) will leave her floundering. Whizzard starts with 3 cr/turn and that's a big deal. There's little else that can reliably handle asset spam, and ultimately little hope beyond trashing everything.