As far as Do's go, they'll be different for everyone so we're going to give you some tips as to how to make your workout as efficient, and beneficial for your body as possible.
Fat Loss
Many people are going to tone their body differently - but the first thing you'll want to do is increase your fat loss during your workouts. The way to do this is to position your heart rate at such a pace that your body is maximally efficient at breaking down grams of fat. One gram of fat is equivalent to 9 kcals, whereas one gram of carbs or protein is only equivalent to 4 kcals. This is why it's so much easier for your body to burn through sugars and carbs, as it takes more energy (comes out in the form of heat, as a kcal - the reason your body temperature increases) to burn through fat.
1. Your heart rate should be anywhere from 55-65% your MAX HR* to spark fat loss,
2. Your workouts should last anywhere from 45 - 60 minutes per day,
3. Your workouts should span on average for 4-5 days per week, for best results,
4. Circuit training or interval training works best.
Toning
First thing you'll want to do is increase your fat calorie loss, by aiming for your workouts to stay, on average, within that fat - loss HR zone. Most of the time people assume doing 1,000 abs per day is going to give you a "6-pack" and that's not the case. If you do any kind of consistent workout whatsoever, you likely have toned muscles underneath a layer of adipose tissue (fat). This isn't saying you're fat by any means, most people have it - especially women. Increasing your fat calorie loss will help. The case is the same for all those thigh machines - no amount of pushing those leg holsters in is going to give you a thigh gap - it comes from fat calorie burning. A couple tips include:
1. Walk-run intervals on the treadmill,
2. Multi-joint weight lifting as opposed to isolated weight lifting,
3. Mixing up your workouts to keep your body on it's toes.
Multi-joint weight lifting would be considered doing squats, lunges, or deadlifts as opposed to using machines to isolate certain groups of muscles. Not only does this increase your hormonal and metabolic responses, both short and long term, but increases the efficiency at which you're toning and strengthening.
Know What You're Doing With Weights
It is a common mistake to believe that high weight/low rep weight lifting is going to be the best for you to burn calories and tone; this isn't necessarily the case.
1. Development of Muscles/Power: High weight/low repetitions
Power: Amount of force you are able to act on relative to your body weight and the rate you can move it at, or in other words, how much weight you lift and how fast you lift it
2. Joint Strength/Stability, Toning: Low weight/high repetitions
Joint Stability: the muscles surrounding a joint capsule are all strengthened equally to provide balance and support
Developing your muscles and power is going to increase your body weight by increasing your lean muscle mass, whereas joint stability and toning is going to increase your lean muscle mass slightly, but is also performed at a HR that falls within the fat-loss zone. When done correctly, major lifts performed for power should increase the HR near it's maximum, or within the performance zone. Performance zone is anywhere from 80 - 100% of your MAX HR.
Body Weight
Your body weight is going to be just as efficient as machines, if not even more so. If you don't have time to run to the gym during the day for whatever reason, I'd suggest doing a circuit of body weight strengthening and agility movements. Something along the lines of:
30 seconds high knees, as fast as you can
10 military-style push-ups
30 seconds butt kicks, as fast as you can
20 squats
30 seconds jog in place
2 minute break
30 seconds high knees, as fast as you can
10 squat jumps
30 seconds jog in place
30 seconds plank, arms extended
20 squats
10 scissor jump lunges, per leg
30 seconds high knees, as fast as you can
2 minute break
30 seconds high knees, as fast as you can
30 squats
30 seconds wall-sits
10 military-style push ups
30 seconds jog in place
3x through, but take your time with the strengthening exercises (squats, pushups, etc.) to help decrease your HR while strengthening. Increase sets over time as you get more confident in the workout. NOTE: the breaks are just as important as the actual exercise. Take that time to get some water, and catch your breath. They're important because they decrease your HR, and these decreases in HR ensure that your average HR for the entirety of the workout stays within that fat burning zone.
*Make sure to talk to your doctor or physical therapist before engaging in any exercise more engaging than your body is used to, as they could increase symptoms of an underlying issue, such as heart problems, or blood pressure.