Fluent Layout

#region Process auto layout

            View.SubviewsDoNotTranslateAutoresizingMaskIntoConstraints();

            var btnPadding = 61;
            var tblPadding = 100;
            var btnWidth = 100;
            var btnHeight = 50;

            // constraints
            View.AddConstraints (
                table.AtTopOf(View, tblPadding),
                table.AtRightOf(View, tblPadding),
                table.AtBottomOf(View, tblPadding),
                table.AtLeftOf(View, tblPadding),

                buttonTop.AtTopOf(View, btnPadding),
                buttonTop.WithSameCenterX(table),
                buttonTop.Width().EqualTo(btnWidth),
                buttonTop.Height().EqualTo(btnHeight),

                buttonRight.AtRightOf(View, btnPadding),
                buttonRight.WithSameCenterY(table),
                buttonRight.Width().EqualTo(btnHeight),
                buttonRight.Height().EqualTo(btnWidth),

                buttonBottom.AtBottomOf(View, btnPadding),
                buttonBottom.WithSameCenterX(table),
                buttonBottom.Width().EqualTo(btnWidth),
                buttonBottom.Height().EqualTo(btnHeight),

                buttonLeft.AtLeftOf(View, btnPadding),
                buttonLeft.WithSameCenterY(table),
                buttonLeft.Width().EqualTo(btnHeight),
                buttonLeft.Height().EqualTo(btnWidth)
            );

            #endregion

Form Grid View

 View.SubviewsDoNotTranslateAutoresizingMaskIntoConstraints();

            var rowSet = new RowSetTemplate()
            {
                TopMargin = 10f,
                BottomMargin = 20f,
                VInterspacing = 10f
            };
            var equalWeightRowTemplate = new RowTemplate()
            {
                HInterspacing = 12f,
                LeftMargin = 6f,
                RightMargin = 24f
            };
            var addressRowTemplate = new RowTemplate()
            {
                HInterspacing = 12f,
                LeftMargin = 6f,
                RightMargin = 24f
            };
            addressRowTemplate.ColumnWeight(0, 0.3f);
            var townAndZipRowTemplate = new RowTemplate()
            {
                HInterspacing = 12f,
                LeftMargin = 6f,
                RightMargin = 24f
            };
            townAndZipRowTemplate.ColumnWidth(1, 120f);

            View.AddConstraints(
                rowSet.Generate(View,
                    new Row(equalWeightRowTemplate, _forceTheWidthView),
                    new Row(equalWeightRowTemplate, fNameLabel, sNameLabel),
                    new Row(equalWeightRowTemplate, fNameField, sNameField),
                    new Row(addressRowTemplate, numberLabel, streetLabel),
                    new Row(addressRowTemplate, numberField, streetField),
                    new Row(townAndZipRowTemplate, townLabel, zipLabel),
                    new Row(townAndZipRowTemplate, townField, zipField),
                    new Row(equalWeightRowTemplate, _debugLabel)
                ));
            View.AddConstraints(_forceTheWidthView.Width().EqualTo().WidthOf(View).Minus(30f));

Form View

View.SubviewsDoNotTranslateAutoresizingMaskIntoConstraints();

            var hMargin = 10;
            var vMargin = 10;


            View.AddConstraints(

                fNameLabel.AtTopOf(View, vMargin + 62),
                fNameLabel.AtLeftOf(View, hMargin),
                fNameLabel.ToLeftOf(sNameLabel, hMargin),

                sNameLabel.WithSameTop(fNameLabel),
                sNameLabel.AtRightOf(View, hMargin),
                sNameLabel.WithSameWidth(fNameLabel),

                fNameField.WithSameWidth(fNameLabel),
                fNameField.WithSameLeft(fNameLabel),
                fNameField.Below(fNameLabel, vMargin),

                sNameField.WithSameLeft(sNameLabel),
                sNameField.WithSameWidth(sNameLabel),
                sNameField.WithSameTop(fNameField),

                numberLabel.WithSameLeft(fNameLabel),
                numberLabel.ToLeftOf(streetLabel, hMargin),
                numberLabel.Below(fNameField, vMargin),
                numberLabel.WithRelativeWidth(streetLabel, 0.3f),

                streetLabel.WithSameTop(numberLabel),
                streetLabel.AtRightOf(View, hMargin),

                numberField.WithSameLeft(numberLabel),
                numberField.WithSameWidth(numberLabel),
                numberField.Below(numberLabel, vMargin),

                streetField.WithSameLeft(streetLabel),
                streetField.WithSameWidth(streetLabel),
                streetField.WithSameTop(numberField),

                townLabel.WithSameLeft(fNameLabel),
                townLabel.WithSameRight(streetLabel),
                townLabel.Below(numberField, vMargin),

                townField.WithSameLeft(townLabel),
                townField.WithSameWidth(townLabel),
                townField.Below(townLabel, vMargin),

                zipLabel.WithSameLeft(fNameLabel),
                zipLabel.WithSameWidth(townLabel),
                zipLabel.Below(townField, vMargin),

                zipField.WithSameLeft(townLabel),
                zipField.WithSameWidth(zipLabel),
                zipField.Below(zipLabel, vMargin),

                debug.WithSameLeft(townLabel),
                debug.WithSameWidth(zipLabel),
                debug.AtBottomOf(View, vMargin)
            );

source
https://www.evernote.com/shard/s147/sh/cb15fbce-6975-4bc5-9366-7bcb3dfcf8e3/69acf044ff8197d6