[gremlin]

............. do I simply slather Vaseline or silicone grease directly onto the battery terminals with the leads connected?

it's best if you remove the cables and coat both battery terminals and cable ends - then reassemble.

[Ice]

 The Bullet Timex has a sealed lead acid battery installed which pretty much puts and end acid induced corrosion.

 To prevent environmentally induced corrosion and rain induced voltage bleed I brush on liquid electrical tape on the battery terminals and case top going outward about 1/2 inch and on the cable ends and cable going up ward about an inch. It seals well and peels off when the need arises.

[barenekd]

Vaseline is good and cheap. The other stuff is fine but more costly.
There are spray electrical cleaners that will be the easiest to apply. Just spray it on, but it will probably more applications to keep the posts clean, as it evaporates pretty quickly. I don't know if it leaves any protectorant behind or not.
Bare

[Craig McClure]

Ya know, I don't do any of the above stuff & have no battery troubles. I do have a AGM type battery which won't corrode, & my G5 Deluxe stays indoors when resting.

[Royalista]

All very well for the spoiled one, but those that have to work for their upkeep do appreciate a touch of vaseline.
Don't misunderstand me: when wet, it is rubbed dry before I take my coat off. You know, first the horse, rider next.