"...be wise as serpents and innocent as doves." (Matt 10.16, ESV)
We live in a day and age where easy access to information, recreation and titillation is forever on the increase. The internet has become both a boon and a bane: it's a vast ocean of resources (thousands upon thousands of new sites are created EVERY day), but inevitably that ocean also contains dangers lurking just below the surface. For every site that can help equip us as God's people (of which there are genuinely plenty), and others that are God-honouring entertainment, there's plenty of others that can lure folks away from Truth and entrap them in easy-to-obtain vices or mindsets.
Of course, the internet is just one example of the world we live in. Media in general (TV/Radio/Magazines/Books) can all help feed an ungodly mindset just as much as enable our walk with Him. The next time you're in a newsagents, take a look at the varied covers on the magazine racks and you'll see the types of gods people live for: beauty, cars, bikes, fashion, careers, health, wealth, pets, houses, sex and more. And take a step away from media, and still we see influences that may affect our and our children's walk with God: opposing mindsets bolstered by recent changes in law, elements of school curriculum (evolution over intelligent design, sex education) and even decisions made by others of God's own people.
So what to do? Shut ourselves away (separatism)? Merge with the culture (syncretism)? Neither, of course: we are "in the world, but not of the world", and the key to doing this successfully lies in Jesus's warning: "...be wise as serpents and innocent as doves" (Matt 10.16). There's our how-to: understanding the culture around us and its thinking ("be wise"), yet remaining untainted by its sinful infection ("be innocent"). Remember: innocent does not mean naive. This way, we may live holy lives for Him, whilst still able to engage with the very people God has called us to share His grace with.
Do you understand the mindsets around you? Get researching, but keep your seatbelt on! Know your limitations, know where you get tempted, then show the people around you something of the grace that He has showered upon you. Maybe it's their turn... But just remember: Clunk, click. Every trip.