If you’re already relatively fit, you should allot 16 to 20 weeks to get trained for a marathon, If you’ve let your fitness routine fall by the wayside a bit, no worries – just factor in an extra three to four weeks to get yourself up to speed – literally. Here’s everything you need to know about marathon training so you can finish strong, no matter when and where you run

Step 1: Customize your training plan

You know what they say about failing to plan… that same idea applies to marathon training. But you can’t just Google “marathon training plans” and choose the first search result you find.

“Training plans aren’t one-size-fits-all,” says Kerry Greer, an expert with EXOS. Consider your fitness level but also your goal (do you want to run the marathon in under four hours? Five? Three?) How many days per week to do you want to work out? On what day do you want to do your long run?

Step 2: Add strength and flexibility training

“Balancing your running with strength training gives your body the stability and power to increase your running efficiency,” . In other words: Getting to the gym will help you to be a better runner. Get in the gym two to three days a week.

Step 3: Focus on technique

Ok, so now you’ve got your workouts scheduled and you’re ready to actually get out there and run. Great. Just be sure you’re running right! “Posture and technique are keys to putting your mind and body in the best position to perform,” says Greer. “Good posture – run tall with your chest up, shoulders back, and feet under your hips – helps your body to work as one unit in proper alignment, warding off injury and helping you to maximize efficiency.”

Step 4: Stay hydrated

You can find plenty of fuel belts and handheld water bottles so you can bring it along with you on runs lasting more than hour. It may be the simplest way to ensure you run your best since being as little as two percent dehydrated can decrease your mental and physical performance by a whopping 20 percent (!) per Greer. (And for those of you looking to lose weight through marathon training, hear this: Staying hydrated gives your metabolism a boost, to boot!)

“On a regular day, try to drink ½ an ounce of water for every pound of body weight,” says Greer. During long runs, stay hydrated by drinking at regular intervals. Though it’s different for everyone, some runners need to drink 8-12 ounces of water, sports drink, or electrolyte beverage every 20 minutes to minimize the effects of dehydration, says Laura Kunces, a nutrition expert with EXOS. More importantly, monitor your thirst throughout the run and continue to drink regularly even as the temps continue to drop and you may not feel as thirsty.

Step 5: Remember to rest.

Everything You Need to Know about Marathon Training

This one may sound easy, but beware: It’s deceptive. Once you get into your training you may find yourself skimping on sleep in order to get in a run. Or, you may be tempted to do two back-to-back tough workouts to get ’em out of the way ahead of that weekend road trip to take in the fall foliage, pick apples-you know, the stuff autumn was made for!

It’s tough to manage training with a day job and (gasp!) having a life outside of both, but it’s all about finding balance and that includes rest days. “Recovery and regeneration activities should be built into your daily routine to help prevent injury and keep you on your training plan,” says Greer. Once a week, do a low intensity activity like a bike ride or – better yet – build an “easy” hike into your weekend getaway. On another day each week, try foam rolling, massage, yoga, or stretching in place of a work out.

Step 6: Taper your training.

Ok, so you’ve been training for about 13 weeks now and you’ve hit the golden 20-mile run on your plan. Congrats! That’s huge. Now it’s time to “taper.” “About two to three weeks before the marathon, steadily decrease how many miles you’re running and the intensity of your training,” says Greer. “This allows your body to adapt, recover, and fully benefit from your training.”

Just be aware that many runners end up with what’s been called “the taper tantrums” where you feel like you should be doing more than you are and you’re a bit cranky and may even feel more sore or tired physically. Know that it’s normal and resist the urge to run more than the training plan suggests!

Step 7: Warm up on race day.

A good warm up is just as important before a race as it is before a training session,” says Greer. As we explained in our quick and effective warmups blog, it helps to increase your core temperature, activate your prime running muscles (hello, quads, hamstrings, calves, and glutes!), and even gets your mind-body connection humming more efficiently. Choose four to six movements to perform at the starting line.