How To Start A New Relationship?

One of the things that always surprises me is how relationships can happen out of the blue.  As a curmudgeon who often goes like a surly camel through dating dry spells of three to four years, each time a relationship crashes and burns, I think it will be my last.  But life always seems to throw a curveball and the next thing I know I'm smack dab in the middle of something I would never have expected even last week.
With the last few relationships I've been in, there have been a lot of don'ts and a few dos I've used to keep fragile new relationships from bursting into flame and spiralling into the equally incendiary dumpster of love.

• Do treat your new relationship as something you will need to earn completely, and patiently maintain.  Forcing a convenient relationship over the framework of one more based on consideration, appreciation and spontaneity kills a lot of the romance and weakens its lifespan.
• Don't mention your ex(es) excessively.  Constantly bringing up someone you no longer (should) care for can undermine what you are trying to establish with your new partner.  While it's inevitable that you'll mention a formerly loved one in passing, there's little point in dragging him or her out of the past to wave around like a stinky swamp fish on every occasion.
• Do let things slide a little.  Your partner isn't perfect, and neither of you should have to expect the other to be.  If you are putting your partner through a lot of stress to keep a home in immaculate condition 24/7, or having him or her drive long distances in order to get together, the tension he or she feels can often come to a boiling point in just a few poor choices of words, and the result can often be sullen anger or exasperated tears.
• Don't let your personal standards down over time.  Think about the things you do before you meet someone for the first time.  How much extra time and effort do you put in compared to when you're just going through the motions?  Though you don't have to pluck every eyebrow hair every day, your partner will still likely appreciate your taking a shower before coming over, or being considerate when you share a common task.
• Do realize you don't have to date your ex again.  It's true that you may have done some bad things in a past relationship, but you're not fated to enact them again.  You don't need to explain what you're being careful to avoid; just let your past relationship lie and let the only things to come from it be unspoken ways to treat your new partner well.
• Don't set expectations you can't keep up.  If you don't like to stay up late and your partner does, don't keep showing up late in the expectations you'll be able to watch a movie together with your eyes plastered open.  If you shouldn't drive over every night because it's 20 miles and your car is a block of Swiss cheese, make it plain that you can't.  Otherwise you won't be in a romantic mood and you'll be wondering why you're even there.  If someone wants to be with you enough, s/he will accept what you are only willing and able to offer.