Nuts/seeds are great for adding weight (real high in calories), you can buy them as cereal as well and have it with soy milk. If you're going to have them alone, try soaking them over night (makes them less dry, easier to eat). Have brown rice/quinoa/couscous or pasta with tins of beans (or tofu) and veg, a jar of tomato (or other) sauce (or tin chopped tomatoes) will make the meal more moist and easy to eat. If you like oatmeal it's great for a quick snack, can add fruit/nuts in there. Smoothies with protein powder are good, can pack in the fruit to get calories up.
When I started I ate too many dry foods, it took ages to eat (especially if you're not particularly hungry) and it was just a lot of work. Now I'm eating about the same amount when I started and it's much easier now.
My advice with stronglifts is to stick to the program. Try not to do much outwith the 3 workouts a week or you'll muscles won't recover before each workout. Even if the weighted exercises seem light to start with you're still burning out your muscles with the bodyweight exercises to failure. If you're keen to do anything extra outwith the program, I'd recommend the following -
1) Dynamic stretches
- I know a few people who have got a groin injury once the squats/deads start getting heavy. These stretches will make you more flexible and will prevent injury. I highly recommend doing this. After a few sessions of doing 10 of each of these stretches (coupled with glute activation stretches
) as a warmup, my mate's groin is about fully recovered.
You can also do them in your days off
2) Grip training - At first exercises like chins/pull-ups, inverted rows will really start to buildup your grip. At the end of your workout it's good to add in some grip training to prepare yourself for when deadlifts get heavy.
3) Chin-ups - If you struggle with these at first (can't do 1 full rep, or can only do a couple), it's one of those exercises you just have to keep trying at. It can be hard to build on just doing them once or twice a week. If you have a bar in the house I'd recommend practicing these frequently.
4) Cardio - By no means necessary and could maybe slow down adding mass a bit, but cardio has a bunch of benefits. Don't do it on the same day as muscle workouts if you want to do it.
My other general advice is keep a training log, and once you get into a routine with your food do a calorie count of an average day and work from there. Consistency is the key!