It's fine to make the switch today. If you're more comfortable being able to keep an eye on Mo during the day, it's also fine to wait until tomorrow.
You do NOT need to wait between feeding and shooting. With Lantus, you test, feed, and shoot all within a few minutes. Lantus onset is not as quick as Novolin. Onset is in about 2 hours for most cats so there's no need to delay between feeding and injecting.
Also, remember the depot! Lantus is a depot insulin. It will take 5 - 7 days to build up in Mo's system so do not expect to see much until the depot is established. It also takes a few cycles for any change in dose to take effect since the depot needs to catch up. In addition, you've reduced the dose from what you were giving with Novolin. It's likely that you will need more insulin that what you're starting out at.
I'd encourage you to read over the sticky notes at the top of the
Lantus board. Lantus is very different pharmacologically than Novolin. Also, you will have a choice of dosing methods so you may want to give that some thought.
A housekeeping note -- remember to add information to your signature that you switched to Lantus and the date. You also have the option of skipping a few lines on. your Novolin tab and indicating that you switched to Lantus. Either way is fine.
Also, if you feel comfortable, you can post on the Lantus board. There are a few more "rules" for posting there but it's a busy forum with lots of experienced Lantus users for support.
