Shot starts 60 seconds before its date that is, (60 + buffer) seconds before auction's
closing time. After shot is started, you can't modify or remove it! You also can't schedule a new
shot if there are less than 60 seconds to go.
Bid responsibly. Remember that a bid is a contract which you will have to keep.
Keep the seller in mind. If this is your first transaction, notify the seller. Some may want to verify the bid. You may also wish to communicate your interest in the auction to the seller. Otherwise, the auction could be prolonged or closed early and your shot will not be a "snipe" or will not be successful at all. Snip will never change your original settings, if auction is prolonged, your bid will be placed much earlier, not a few seconds before closing.
Check the exact time the auction ends and decide how many seconds before the end you
want to bid. You can determine how long the average shoot takes at
Snip shots statistics. Note that shot's time depends also on the day of the week - e.g. on Sundays, when most auctions are ending, shots can be slower than in other days.
Remember, if you bid too early, a sniper with more patience will win.
If you wait too long, you may not be able to complete your shot before the auction ends.
After all, using Snip is a form of gambling ;-)
There's one important thing one must be aware of:
There's a bit of luck involved in sniping and there's no second
chance! If something, anything goes wrong at the moment of the
"shot", you lose. Please be aware of this when sniping.