Hi all,
First post...so go easy 
My wife has suggested that she would like me to be more assertive in bed. Not to the point of domination (I don't think), just being in change, making the decisions and getting what I want. I'm happy to give it a go, and like the sound of it, but I'm a bit stumped. I need to insperation.
Could anyone suggest some actions and phrases to get me going.
Cheers
I think you need to find her trigger words first, ask her what she likes to be called in the bedroom, some people like to just be ordered around so simply saying “get on your knees” is enough to get them breathing heavy, others like a more gentle approach such as “slowly remove your bra...” and others like a very rough and dominant terms to get a spark going.
But if she wants you to be more assertive then possibly when she gives you the eye you should place your hand on the side of her neck and kiss her deeply, until you can start to work your hands over her body and really get things flowing. Ask her in a playful conversation what she likes in the bedroom and what names she likes, does she want to call you by your nameC a nickname or something like “sir” “master” or “daddy” which seem the most common phases.
Once you have a base of what words and terms she likes and how she likes to be ordered you can usually put two and two together and find a way to achieve what she wants. It shows she’s comfortable to communicate already which is excellent, and you coming here for advice proves you care for her which so talk more, play around with a few scenarios and maybe some light bondage play if she likes this. But always check to see if someone is comfortable with this. Maybe watch some sexual movies as they tend to make the Male lead very assertive and empowering such as fifty shades (I know a lot of people love and hate the movies but worth a watch).
Look up some beginner guides online to being dominant and try and make the moves when you notice she’s in the mood. If she starts to run her leg against yours in bed, or becomes very touchy feely etc then respond with slight gestures (kissing, petting etc). After a while in most relationships you can almost tell just by being in the same room! But unfortunately as everyone is different you can’t just get a book on how to initiate something. But enjoy the exploration and have fun, as long as your both laughing and having fun it’s exactly how sex should be.
What lil_known said sounds perfect.
When Mr fox and I got together I asked the same of him, I was always more submissive but he was less experienced so wanted to ease into things, find our rhythm slowly and it's evolved perfectly for us. I'd suggest small changes to start with, do what you usually do but when she (for example) goes to touch you stop her and guide her hand to herself (or vise versa) or begin kissing, undressing, and tell her "I want you to XXX" it's less about orders and forcing more saying I want this/I want to do this/ now we are going to do *** my way. Remember though if she seems hesitant or says no then move on, this isn't the time to introduce something you want and she's not comfortable with but doing the things she likes but on your terms.
^+1
Also to add to my previous message, when someone does ask to be more assertive and take charge it’s not a free pass to use them like a doll. As above, it’s subtle changes which slowly evolve and eventually things just click. Communication is key and as soon as things get a bit hesitant or unsure then move on as fox said.
Another way I've found is send suggestions throughout the day. I might send a naughty text telling her what I'm going to do to her when I get home or what I want her to do to me. I often get replies like "Oh really" or "We'll see" this is effectively the green light.
If I'm with her I might gently push her against the wall and tell her what's going to happen then (or later) or pull her in to me from behind and touch her, again the response provided gives an instant indication of whether she's game.
As others have said you find your own way of doing things and knowing what's going to work.
Thanks for the replies. It's definitely more about me being in control so she doesn't have to worry about making decisions on top of everything she has to worry about in normal life.
Problem is that I tend to go along with things generally because I don't want to cause waves and want the easy life.
This isn't about being aggressive, doing things against wishes or being abusive. So no spanking or calling her names.
It's more about me making the decisions within the normal boundaries we have and probably being more vocal and a bit more direct.
I think the gist is "tonight we're doing things my way" and just being more direct, honest and vocal 😀
We're in the reverse type relationship - I dominate over him.
When we started, I just blindfolded him and told him 'not a single word from you' . I slowly introduced my skinny belt and stuff from kitchen while used his neckties to tie him up. 
I think you can try that if you like. Spanking is not abusive as long as you're both on the same page.
Communication, communication, communication